• ARRL Propagation Bulletin

    From Daryl Stout@316:36/20 to All on Fri Mar 31 22:22:48 2023

    SB PROP @ ARL $ARLP013
    ARLP013 Propagation de K7RA

    ZCZC AP13
    QST de W1AW
    Propagation Forecast Bulletin 13 ARLP013
    From Tad Cook, K7RA
    Seattle, WA March 31, 2023
    To all radio amateurs

    SB PROP ARL ARLP013
    ARLP013 Propagation de K7RA

    Solar activity increased this week. Average daily sunspot number
    rose from 68 to 112.6, and average daily solar flux changed from
    145.6 to 156.1.

    A new sunspot group emerged on March 24, two more on March 26 and
    27, and three on March 29.

    Due to solar wind and a geomagnetic disturbance at the beginning of
    the reporting week, average daily planetary A index increased from
    10.6 to 23.3, while average middle latitude A index went from 8.4 to
    13.7. Many reports of aurora came in this week, some down to lower
    latitudes in North America.

    Predicted solar flux is 135 on March 31, 130 on April 1-6, 132 on
    April 7-8, then 130, 132, 135 and 135 on April 9-12, then 140, 145
    and 148 on April 13-15, then 150, 150, 155, 155 and 158 on April
    16-20, 160 on April 21-23, then 155, 145 and 145 on April 24-26, and
    135 on April 27 through May 1, then 132 on May 2-5, then 130, 132,
    135 and 135 on May 6-9.

    Predicted planetary A index is 18, 16, 12, 10 and 8 on March 31
    through April 4, then 5 on April 5-9, then 15, 12, 8 and 5 on April
    10-13, 8 on April 14-15, then 12, 20, 15 and 5 on April 16-19, then
    20, 15 and 10 on April 20-22, 8 on April 23-24, 5 on April 25-26,
    then 12, 15, 10 and 8 on April 27-30, and 5 on May 1-6, then 15, 12
    and 8 on May 7-9.

    Weekly Commentary on the Sun, the Magnetosphere, and the Earth's
    Ionosphere - March 30, 2023 from OK1HH.

    "The strong geomagnetic storm on 23-24 March was not expected.
    Moreover, it was classified as a G4, making it the most intense in
    almost 6 years. The source of the solar wind was not identified with
    certainty, but a large coronal hole in the south, near the central
    meridian, could not be missed.

    "As a consequence of the disturbance, the ionosphere first
    experienced a rise in the critical frequencies of the F2 layer on 23
    March, followed by a significant drop on 24-25 March. Their normal
    values started to be registered again only after 26 March.

    "Energetic flares are a reliable indicator of the increase in solar
    activity. On March 29, the seventh X-class flare of the year was
    registered. Yet a total of seven were registered in 2022 and only
    two in 2021.

    "Most of the sunspots are now on the western half of the solar disk.
    As they gradually set, total solar activity will first decrease over
    the next week before rising again."

    Here are articles about solar activity as an existential threat:

    https://bit.ly/3M28RQv

    https://bit.ly/42W7xo4

    https://bit.ly/40Qf6Lc

    Nice sunspot video, before the aurora:

    https://bit.ly/3K2alHX

    AA7FV wrote on March 25:

    "There was a 6-meter opening from Arizona to VK on March 24. I
    received VK7HH in Tasmania at 2028 UTC on WSPR; he was using just
    0.2 watts (200 mW)."

    VK7HH responded:

    "Yes, that WSPR spot was from my remote station running 200 mW from
    a Zacktek WSPR TX into a 1/2 wave vertical antenna. HASL 931m."

    AA7FV wrote:

    "For reference, my 50 MHz antenna is a Cushcraft 1/2-wave vertical,
    the Ringo AR6, with its base at about 10 feet above ground. The
    location here is 870m asl but I'm in the valley, just outside
    Tucson. The receiver is an ancient Icom PCR1000, but with a preamp.
    I monitor 6m 24/7, but rarely hear any signals at all, and when I do
    hear something it's usually from someone else in Arizona."

    On March 25, Jon, N0JK wrote:

    "Worked VP8NO in GD18 today on 6 Meter FT8 at 1905 UTC. de N0JK
    EM28 in Kansas."

    Jon was using a portable 2 element Yagi and running 50 watts.

    Here is an article about a "Hole" in the Sun:

    https://www.space.com/solar-flare-coronal-hole-space-weather

    Send your tips, reports, observations, questions and comments to
    k7ra@arrl.net. When reporting observations, don't forget to tell us
    which mode you were operating.

    For more information concerning shortwave radio propagation, see http://www.arrl.org/propagation and the ARRL Technical Information
    Service at http://arrl.org/propagation-of-rf-signals . For an
    explanation of numbers used in this bulletin, see http://arrl.org/the-sun-the-earth-the-ionosphere .

    An archive of past propagation bulletins is at http://arrl.org/w1aw-bulletins-archive-propagation . More good
    information and tutorials on propagation are at http://k9la.us/ .

    Instructions for starting or ending email distribution of ARRL
    bulletins are at http://arrl.org/bulletins .

    Sunspot numbers for March 23 through 29, 2023 were 73, 108, 105,
    125, 128, 114, and 135, with a mean of 112.6. 10.7 cm flux was 151,
    157.5, 160.3, 159.4, 158.2, 158.7, and 147.8, with a mean of 156.1.
    Estimated planetary A indices were 60, 66, 15, 8, 3, 5, and 6, with
    a mean of 23.3. Middle latitude A index was 28, 40, 12, 6, 2, 4, and
    4, with a mean of 13.7.
    NNNN
    /EX
    --- SBBSecho 3.14-Win32
    * Origin: The Thunderbolt BBS - Little Rock, Arkansas (316:36/20)
  • From Daryl Stout@316:36/20 to All on Fri Apr 7 17:29:35 2023

    SB PROP @ ARL $ARLP014
    ARLP014 Propagation de K7RA

    ZCZC AP14
    QST de W1AW
    Propagation Forecast Bulletin 14 ARLP014
    From Tad Cook, K7RA
    Seattle, WA April 7, 2023
    To all radio amateurs

    SB PROP ARL ARLP014
    ARLP014 Propagation de K7RA

    Average solar flux and sunspot numbers were way down this week.
    Sunspot numbers were down by half, from 112.6 last week to 53.4.
    Average daily solar flux declined from 156.1 to 132.5.

    Geomagnetic indicators were lower too. Average daily planetary A
    index from 23.3 last week to 15 in this bulletin, and average daily
    middle latitude A index from 13.7 to 11.7.

    The April 1 middle latitude A index of 11 is my guess. The middle
    latitude A index for April 1 was not available.

    Predicted solar flux is 140 on April 7 and 8, 135 on April 9 to 11,
    140, 145 and 130 on on April 12 to 14, 130 on April 14, 135 on April
    15 to 17, 140 on April 18 to 20, 135 on April 21 to 23, then 130,
    125 and 120 on April 24 to 26, 115 on April 27 to 29, 125 on April
    30, 120 on May 1 and 2, 115 on May 3 and 4, then 110 on May 5 to 7,
    and 115, 120, 125 and 130 on May 8 to 11, then 135 on May 12 to 14,
    and 140 on May 15 to 17.

    Predicted planetary A index is 5 on April 7 to 10, then 8, 8 and 5
    on April 11 to 13, 8 on April 14 and 15, then 12, 10 and 15 on April
    16 to 18, then 5, 20, 15 and 10 on April 19 to 22, 5 on April 23 to
    25, then 15 and 18 on April 26 and 27, 15 on April 28 and 29, 8 on
    April 30, 10 on May 1 and 2, 8 on May 3, then 5 on May 4 to 6, then
    12, 10, 8 and 5 on May 7 to 10, 8 on May 11 and 12, then 10, 12, 15,
    5 and 20 on May 13 to 17.

    Weekly Commentary on the Sun, the Magnetosphere, and the Earth's
    Ionosphere -- April 6, 2023 from F.K. Janda, OK1HH.

    "On March 29, another solar flare of category X1.2 was observed. It
    came from the AR3256 sunspot group near the southwestern limb of the
    Sun.

    This year, in just three months, we've already seen seven X-class
    flares, the same as all of last year. There are still about two
    years to go before the cycle peak.

    On the morning of March 31, a solar wind stream hit Earth,
    triggering a minor G1-class geomagnetic storm. A relatively quiet
    weekend followed.

    Then new sunspot group AR3270 emerged in the southern part of the
    solar disk. It grew rapidly, its two dark cores, larger than Earth,
    indicating an unstable magnetic field. If they merge an eruption
    would likely follow. It would probably be a geoeffective eruption
    because the sunspot was directly opposite the Earth.

    After the AR3270 sunspot group dips behind the southwestern limb of
    the solar disk this weekend, there should be a temporary drop in
    overall solar activity, accompanied by a string of geomagnetically
    quieter days.

    As the irregular occurrence of higher geomagnetic activity results
    in irregular changes in shortwave propagation conditions, the
    subsequent evolution should be more regular and predictable."

    This video from Tamitha Skov came out right after last week's
    bulletin:

    https://youtu.be/F8ERhLiOK88

    More sun fun:

    https://youtu.be/VWhhSWjDJtw

    https://bit.ly/41aolq2

    Don't worry:

    https://bit.ly/3zCtg74

    On April 5 from 1723 to 1746 UTC, Tom, WA1LBK in Fall River,
    Massachusetts copied HC1MD/2 in Ecuador on 6 meter FT8. Check HC1MD
    on QRZ.com for some beautiful photos by Rick, NE8Z.

    https://bit.ly/3zBm5wa

    This weekend is the CW portion of the Japan International DX
    Contest.

    See http://jidx.org/

    Send your tips, reports, observations, questions and comments to
    k7ra@arrl.net. When reporting observations, don't forget to tell us
    which mode you were operating.

    For more information concerning shortwave radio propagation, see http://www.arrl.org/propagation and the ARRL Technical Information
    Service at http://arrl.org/propagation-of-rf-signals . For an
    explanation of numbers used in this bulletin, see http://arrl.org/the-sun-the-earth-the-ionosphere .

    An archive of past propagation bulletins is at http://arrl.org/w1aw-bulletins-archive-propagation . More good
    information and tutorials on propagation are at http://k9la.us/ .

    Instructions for starting or ending email distribution of ARRL
    bulletins are at http://arrl.org/bulletins .

    Sunspot numbers for March 30 through April 5, 2023 were 99, 61, 23,
    54, 56, 44, and 37, with a mean of 53.4. 10.7 cm flux was 140.3,
    129.3, 125.3, 126.9, 133.6, 135.7, and 136.6, with a mean of 132.5.
    Estimated planetary A indices were 17, 21, 13, 15, 15, 13, and 11,
    with a mean of 15. Middle latitude A index was 11, 17, 11, 13, 11,
    10, and 9, with a mean of 11.7.
    NNNN
    /EX
    --- SBBSecho 3.14-Win32
    * Origin: The Thunderbolt BBS - Little Rock, Arkansas (316:36/20)
  • From Daryl Stout@316:36/20 to All on Fri Apr 14 12:45:33 2023

    SB PROP @ ARL $ARLP015
    ARLP015 Propagation de K7RA

    ZCZC AP15
    QST de W1AW
    Propagation Forecast Bulletin 15 ARLP015
    From Tad Cook, K7RA
    Seattle, WA April 14, 2023
    To all radio amateurs

    SB PROP ARL ARLP015
    ARLP015 Propagation de K7RA

    Solar activity was up for this reporting week, April 6-12.

    Seven new sunspot groups appeared, one on April 6, another on April
    9, two more on April 10, another on April 11, and two more on April
    12. Then on Thursday, April 13, three new sunspot groups emerged.
    The sunspot number rose to 154, the highest value in the past month.

    Average daily sunspot number rose from 53.4 to 70.6, and average
    daily solar flux increased from 132.5 to 141.

    On Thursday, the noon solar flux reading was 159.5 and was well
    above the average for the previous seven days, perhaps indicating an
    upward trend.

    Geomagnetic conditions were calm, with average daily planetary A
    index dropping from 15 to 7.6, and the middle latitude average from
    11.7 to 6.4.

    Predicted solar flux was 155 and 160 on April 13-14, and 165 on
    April 15-16.

    The Thursday prediction was well above that.

    Predicted solar flux is 168 on April 14-16, 165 and 160 on April
    17-18, 155 on April 19-22, 158 on April 23, 155 on April 24-25, then
    152, 148, 145 and 142 on April 26-29, 140 on April 30 and May 1, 142
    and 140 on May 2-3, 135 on May 4-5, then 130, 140, 145, 150, 152,
    155 and 158 on May 6-12, then 160 on May 13-15, and 150 and 152 on
    May 16-17, 155 on May 18-19, then 158, 155 and 155 on May 20-22.

    Predicted planetary A index is 8, 12, 10 and 8 on April 14-17, 5 on
    April 18-20, then 8 and 10 on April 21-22, 5 on April 23-25, then 15
    and 18 on April 26-27, 15 on April 28-30, then 12 and 10 on May 1-2,
    8 on May 3-4, 5 on May 5-6, then 8, 10 and 8 on May 7-9, and 5 on
    May 10-13, then 10, 15 and 5 on May 14-16, 20, 15 and 10 on May
    17-19, and 5 on May 20-23.

    Spaceweather.com released this news on Wednesday:

    "Evidence is mounting that Solar Cycle 25 might peak much earlier
    than expected. New research by a leading group of solar physicists
    predicts maximum sunspot activity in late 2023 or early 2024 with a
    peak that could be twice as strong as the previous solar cycle."

    Look in the Spaceweather archive for April 12-13 to read more. It
    is all explained in this scientific paper:

    https://bit.ly/41gZnW4

    I noticed some very odd 10 meter propagation at 2000 UTC on April
    11. Running FT8 and a one wavelength end fed wire at my home in
    Seattle, the only stations that heard me according to
    pskreporter.info were one in New Zealand, another in Hawaii, and in
    North America, only 5 stations (NK5B, AD4ES, K4RMM, KB4FB and AA4CB)
    in Florida, all within a 200 mile strip from 2,512 to 2,712 miles
    from me. Checking again at 2015 UTC, it was still the same. It
    looked quite dramatic on the pskreporter.info map.

    Weekly Commentary on the Sun, the Magnetosphere, and the Earth's
    Ionosphere - April 13, 2023, from F.K. Janda, OK1HH.

    "Relatively frequent C-class solar flares, sporadic M-class flares
    in one or two sunspot groups, and the appearance of two or three
    relatively small coronal holes - that's how the Sun looked between
    April 6 and 13.

    "The solar wind speed dropped to 340 km/s by April 9, rose
    significantly to 550 km/s on April 10, and then slowly dropped
    again. The Earth's magnetic field was unsettled on April 10, then
    mostly calm on the other days.

    "MUF values were slightly higher on 10 April. This was followed by
    11 April with irregular daily MUF and irregular occurrences of
    attenuation. Since 12 April onward there was a transition to a
    regular daily course of ionospheric parameters.

    "Now we can expect higher solar activity in the southern hemisphere.
    The rise should continue in the coming days at first. A slight
    decrease will follow after the weekend.

    "A slight increase in geomagnetic activity with consequent
    fluctuations in shortwave propagation conditions can be expected
    rather since the middle of next week."

    Here is a video about the Termination Event:

    https://youtu.be/wcJdNBow_5s

    A story on NASA using AI to predict geomagnetic storms:

    https://bit.ly/3mws16y

    Here is a story about Radio Blackout:

    https://bit.ly/3UCz8ar

    Mike Mason, WB4MM in Daytona Beach, Florida wrote:

    "On April 9 2023 FT8 mode 12 meters beginning at 2254 UTC and ending
    at 2328 UTC I worked 12 JA stations plus 2 South Korean stations in
    a row. I was calling CQ AS WB4MM EL99.

    "My station has 100 watts to an attic 15M dipole. I believe the SFI
    at the time was 135. Not sure of the type of prop. This occurred
    within an hour of sunset at my QTH."

    Send your tips, reports, observations, questions, and comments to k7ra@arrl.net. When reporting observations, don't forget to tell us
    which mode you were operating.

    For more information concerning shortwave radio propagation, see http://www.arrl.org/propagation and the ARRL Technical Information
    Service at http://arrl.org/propagation-of-rf-signals . For an
    explanation of numbers used in this bulletin, see http://arrl.org/the-sun-the-earth-the-ionosphere .

    An archive of past propagation bulletins is at http://arrl.org/w1aw-bulletins-archive-propagation . More good
    information and tutorials on propagation are at http://k9la.us/ .

    Instructions for starting or ending email distribution of ARRL
    bulletins are at http://arrl.org/bulletins .

    Sunspot numbers for April 6 through 12, 2023 were 33, 38, 49, 52,
    92, 103, and 127, with a mean of 70.6. 10.7 cm flux was 137.1,
    136.3, 135.9, 140.3, 139.8, 143.4, and 154, with a mean of 141.
    Estimated planetary A indices were 9, 8, 6, 6, 14, 6, and 4, with a
    mean of 7.6. Middle latitude A index was 7, 7, 5, 5, 11, 6, and 4,
    with a mean of 6.4.
    NNNN
    /EX
    --- SBBSecho 3.14-Win32
    * Origin: The Thunderbolt BBS - Little Rock, Arkansas (316:36/20)
  • From Daryl Stout@316:36/9 to All on Fri Apr 21 13:52:33 2023

    SB PROP @ ARL $ARLP016
    ARLP016 Propagation de K7RA

    ZCZC AP16
    QST de W1AW
    Propagation Forecast Bulletin 16 ARLP016
    From Tad Cook, K7RA
    Seattle, WA April 21, 2023
    To all radio amateurs

    SB PROP ARL ARLP016
    ARLP016 Propagation de K7RA

    Again this week sunspot numbers and solar flux were higher than the
    week before.

    Average daily sunspot numbers more than doubled, from 70.6 to 146.9,
    and average daily solar flux increased from 141 to 164.5. Both
    figures represent a substantial increase in solar activity.

    Planetary A index averages went from 7.6 to 8.1, while middle
    latitude A index advanced from 6.4 to 7.3.

    Three new sunspot groups emerged on April 13, one more on April 16,
    and another on April 17.

    Predicted solar flux over the next few weeks is 145, 140 and 135 on
    April 21-23, 130 on April 24-25, 125 on April 26-27, 160 on April
    28-29, 165 on April 30, 172 on May 1-3, 170 on May 4, 172 on May
    5-7, 178 on May 8, 182 on May 9-12, then 175, 178 and 170 on May
    13-15, 168 on May 16-17, 175 on May 18, then 172 on May 19-21, then
    168 and 162 on May 22-23, 160 on May 24-26, 165 on May 27, and 172
    on May 28-30.

    Predicted planetary A index is 20, 16, 12 and 8 on April 21-24, 5 on
    April 25-27, 15 on April 28-30, then 12 and 10 on May 1-2, 8 on May
    3-4, 5 on May 5-6, 12 on May 7, 5 on May 8-10, then 8 on May 11-12,
    5 on May 13-18, then 10, 8, 5 and 5 on May 19-22, 15 and 18 on May
    23-24, 15 on May 25-27, then 12 and 10 on May 28-29.

    Weekly Commentary on the Sun, the Magnetosphere, and the Earth's
    Ionosphere - April 20, 2023 from OK1HH.

    "Of the fifteen sunspot groups observed over the past week, AR3272
    and AR3282 were the source of most of the flares. Both had a
    beta-gamma magnitude configuration. 61 C-class flares and 4 M-class
    flares were observed.

    "The partial halo CMEs on 15 and 16 April were the source of
    particles that reached Earth on 18 April, when the solar wind speed
    increased abruptly at 1308 UTC and a geomagnetic disturbance
    developed.

    "A positive phase of the ionospheric disturbance was recorded on the
    afternoon of 18 April, followed by a negative phase on 19 April.
    This was followed on 20 April with a significant increase in f0F2
    and improved shortwave propagation conditions before noon UTC.

    "The outlook looks promising for the first half of May, when solar
    activity should increase further."

    Dan Handa, W7WA commented on the news last week about the current
    solar cycle reaching a peak earlier than predicted, perhaps by the
    end of this year.

    I told him I hoped it would not peak early, because I wanted to see
    several more years of increasing activity.

    Dan sent a very detailed graph of Solar Cycle 19 from 1954 to 1966,
    and wrote: "I have read, and more than once, a slow rise means a low
    sunspot max. The previous Solar Cycle 24 took five years to reach a
    relatively low maximum. A rapid increase can mean a high sunspot
    maximum. The granddaddy of our lifetime, Solar Cycle 19 peaked in
    three years!"

    I did not know this.

    In a subsequent message, Dan further commented:

    "There was a lot of short term variation in the Solar Cycle 19
    sunspot number, just like we're seeing now. From the graph the
    timing of the Solar Cycle 19 peak can be defined three different
    ways: the daily peak, the smoothed monthly peak or the smoothed
    yearly peak, take your pick."

    Another Solar Cycle 19? Many hams have dreamed of this for the past
    six decades.

    Dale, WB6MMQ reported that the solar images in the ARRL Letter with
    a preview of our Friday bulletin show a blank Sun. I wasn't sure
    what he was talking about, but now I realize this must be a stock
    image (not from me!) used in the Letter.

    I sent Dale links to some recent images from Spaceweather.com:

    https://www.spaceweather.com/images2023/20apr23/hmi1898.gif

    https://www.spaceweather.com/images2023/19apr23/hmi1898.gif

    https://www.spaceweather.com/images2023/18apr23/hmi1898.gif

    https://www.spaceweather.com/images2023/17apr23/hmi1898.gif

    I hope this clears up the confusion.

    An odd correlation between an ancient epidemic and solar activity:

    https://bit.ly/3Lsqfxf

    A story about a possible early Solar peak:

    https://www.space.com/sun-solar-maximum-may-arrive-early

    A story about possible M-class solar flares:

    https://bit.ly/3KVc1n1

    Send your tips, reports, observations, questions and comments to
    k7ra@arrl.net. When reporting observations, don't forget to tell us
    which mode you were operating.

    For more information concerning shortwave radio propagation, see http://www.arrl.org/propagation and the ARRL Technical Information
    Service at http://arrl.org/propagation-of-rf-signals . For an
    explanation of numbers used in this bulletin, see http://arrl.org/the-sun-the-earth-the-ionosphere .

    An archive of past propagation bulletins is at http://arrl.org/w1aw-bulletins-archive-propagation . More good
    information and tutorials on propagation are at http://k9la.us/ .

    Instructions for starting or ending email distribution of ARRL
    bulletins are at http://arrl.org/bulletins .

    Sunspot numbers for April 13 through 19, 2023 were 154, 153, 151,
    155, 162, 140, and 113, with a mean of 146.9. 10.7 cm flux was
    159.5, 171.3, 175.8, 177.8, 166.6, 153.2, and 147, with a mean of
    164.5. Estimated planetary A indices were 6, 7, 9, 4, 6, 13, and 12,
    with a mean of 8.1. Middle latitude A index was 5, 10, 8, 4, 6, 9,
    and 9, with a mean of 7.3.
    NNNN
    /EX
    --- SBBSecho 3.20-Win32
    * Origin: The Thunderbolt BBS - Little Rock, Arkansas (316:36/9)
  • From Daryl Stout@316:36/9 to All on Fri Apr 28 12:43:34 2023

    SB PROP @ ARL $ARLP017
    ARLP017 Propagation de K7RA

    ZCZC AP17
    QST de W1AW
    Propagation Forecast Bulletin 17 ARLP017
    From Tad Cook, K7RA
    Seattle, WA April 28, 2023
    To all radio amateurs

    SB PROP ARL ARLP017
    ARLP017 Propagation de K7RA

    At 0134 UTC on April 27, The Australian Space Weather Forecasting
    Centre issued a geomagnetic disturbance warning:

    "An equatorial coronal hole is currently elevating solar wind
    speeds. Combined with the anticipated impact from a recent CME on
    April 27, geomagnetic activity is expected to be at G0-G1 levels
    over April 27-28, with a slight chance of an isolated period of G2."

    Solar and geomagnetic indicators moved in opposite directions this
    week. Average daily sunspot numbers over April 20-26 made a dramatic
    drop from 146.9 to 91.4, and average daily solar flux from 164.5 to
    139.4.

    Average daily planetary A index more than tripled from 8.1 to 26.9,
    while average middle latitude A index more than doubled from 7.3 to
    15.6.

    Solar wind and explosions caused all this grief.

    Spaceweather.com reported that on April 21, a large magnetic
    filament on the Sun exploded, hurling debris toward Earth.

    Later they reported that on April 23 at 1737 UTC a CME hit Earth,
    sparking a severe G4-class geomagnetic storm. Aurora was visible as
    far south as southern New Mexico and Texas.

    The planetary K index went as high as 8 over April 23-24.

    Predicted solar flux over the next month is 135 on April 28-30, 140
    on May 1-2, 135 on May 3-4, 140 on May 5-6, then 145, 150, 155, 160
    and 165 on May 7-11, 170 on May 12-13, then 165, 160, 155, 150, 145
    and 140 on May 14-19, 135 on May 20-21, 130 and 125 on May 22-23,
    120 on May 24-25, then 125, 130 and 135 on May 26-28, 140 on May 29
    through June 2, then 145, 150, 155, 160, and 165 on June 3-7.

    Predicted planetary A index is 25, 16 and 12 on April 28-30, 8 on
    May 1-5, 12 and 10 on May 6-7, 8 on May 8-9, then 5, 5 and 12 on May
    10-12, 5 on May 13-15, 8 on May 16-17, 5 on May 18-22, then 15 and
    18 on May 23-34, and 15 on May 25-27, then 12 and 10 on May 28-29, 8
    on May 30-31, then 5, 5 and 12 on June 1-3, and 5 on June 4-6.

    Weekly Commentary on the Sun, the Magnetosphere, and the Earth's
    Ionosphere - April 27, 2023 from F.K. Janda, OK1HH.

    "The most important event of the last seven days was the solar flare
    on 21 April with a maximum at 1812 UTC (1744 - 1857 UT). It was a
    long duration event (LDE), accompanied by the ejection of a cloud of
    coronal plasma into space, at a location on the Sun where there is a
    high probability of the cloud hitting the Earth. It is therefore not
    surprising that all forecast centres agreed in predicting the
    impending disturbance.

    "The speed of the solar wind jumped up on 23 April at 1703 UTC,
    after which a geomagnetic disturbance began to develop. It was much
    stronger than expected (max K=8 and G4 instead of the expected K=6
    and G1-2). Auroras were observed with two maxima - in Europe on 23
    April mainly between 1900-2100 UTC and in North America on 24 April
    between 0300-0400 UTC.

    "Thereafter, propagation conditions deteriorated significantly,
    especially on 24-25 April, with one interesting variation of the
    evolution: the calming of the geomagnetic field on the morning of 25
    April UTC was followed by a further development of the disturbance
    with an albeit shorter but significant improvement. The return of
    the critical frequencies of the F2 layer and the improvement of
    shortwave propagation conditions toward the mean continued only
    slowly in the following days, as intervals of increased geomagnetic
    activity occurred daily. The lowest f0F2 were observed on the night
    of 23-24 April. The following night was slightly better."

    Rocky Riggs, W6RJK in Truckee, California wrote:

    "I was not very active until recently when I was introduced to POTA.
    The park I frequent the most would typically give me 40-60 contacts
    in a 2 hour period.

    "On Monday, the 24th, I went to the same park, and in 30+ minutes
    had no contacts and couldn't hear anyone either. I later found out
    that the solar storm was causing most of our radio problems. Until
    then, I had never considered much about solar flares, or how the Sun
    influences radio propagation. Now, finally, I'm trying to learn as
    much as I can. The K7RA Solar Update in the ARRL Newsletter is
    FANTASTIC, and will be my source going forward to help me learn and
    understand.

    "Here's my question. Is there a 'real time' place where I can go to
    determine if a particular band has good propagation (I typically use
    20m and 40m)?

    "You know, like before I go out and get all set up and it's a 'goose
    egg.'"

    I replied:

    "I recommend pskreporter.info, and look on the map screen for FT8
    signals from your grid square and where they are heard. You don't
    have to use FT8 to use this.

    "You can also check for the 'country of callsign' option with your
    own or any callsign. When I do this for 10 meters, this week it has
    been showing no propagation from my area, but lots of 10 meter
    propagation in the south and across the east coast.

    "I use FT8 a lot to study propagation."

    Angel Santana, WP3GW in Trujillo Alto, Puerto Rico wrote:

    "Been doing a lot of FT8 these months. More DXpeditions are
    including its operation. Just last week on April 16th at 1939 UTC
    worked VU7W and in WARD April 18th T30UN at 0721 on 40m and 0735 on
    30m, the two ATNOs."

    (I think WARD refers to World Amateur Radio Day, and of course ATNO
    refers to All Time New One, something I did not know until a few
    years ago. -K7RA)

    "But on the 20th, at 0800 UTC, saw stations on 10 meters, normally
    you do not hear them on any mode at that time. Then I began to call
    them and a few from Europe contacted me. Then at about 0845 UTC,
    'poof' they disappeared.

    "These are the things that make me say that it is because of the
    'crazy prop' (la propa loca)."

    Tomas Hood, NW7US has a monthly propagation column in CQ Magazine,
    which is a great resource. In the March issue he writes about the
    promising progress of Solar Cycle 25.

    Another great resource is Chapter 19, the "Propagation of Radio
    Signals" in the 2023 100th edition of the ARRL Handbook. It contains
    the most comprehensive treatment of radio propagation I have ever
    seen and goes on for 38 pages.

    Aurora observed in China:

    https://bit.ly/41KyY3w

    Aurora in Iowa:

    https://bit.ly/3Nlvy2S

    An article explaining aurora:

    https://bit.ly/3n7ROm2

    A Science & Tech article about Sun science:

    https://bit.ly/429Sqq9

    From 2017, a NASA sunspot video:

    https://www.exploratorium.edu/video/nasa-life-sunspot

    Send your tips, reports, observations, questions and comments to
    k7ra@arrl.net. When reporting observations, don't forget to
    tell us which mode you were operating.

    For more information concerning shortwave radio propagation, see http://www.arrl.org/propagation and the ARRL Technical Information
    Service at http://arrl.org/propagation-of-rf-signals . For an
    explanation of numbers used in this bulletin, see http://arrl.org/the-sun-the-Earth-the-ionosphere .

    An archive of past propagation bulletins is at http://arrl.org/w1aw-bulletins-archive-propagation . More good
    information and tutorials on propagation are at http://k9la.us/ .

    Instructions for starting or ending email distribution of ARRL
    bulletins are at http://arrl.org/bulletins .

    Sunspot numbers for April 20 through 26, 2023 were 97, 114, 87, 86,
    88, 87, and 81, with a mean of 91.4. 10.7 cm flux was 147, 151.2,
    141.2, 135.2, 133.9, 130.7, and 136.5, with a mean of 139.4.
    Estimated planetary A indices were 5, 9, 7, 66, 76, 10, and 15, with
    a mean of 26.9. Middle latitude A index was 5, 8, 6, 32, 39, 7, and
    12, with a mean of 15.6.
    NNNN
    /EX
    --- SBBSecho 3.20-Win32
    * Origin: The Thunderbolt BBS - Little Rock, Arkansas (316:36/9)
  • From Daryl Stout@316:36/9 to All on Fri May 5 08:56:50 2023

    SB PROP @ ARL $ARLP018
    ARLP018 Propagation de K7RA

    ZCZC AP18
    QST de W1AW
    Propagation Forecast Bulletin 18 ARLP018
    From Tad Cook, K7RA
    Seattle, WA May 5, 2023
    To all radio amateurs

    SB PROP ARL ARLP018
    ARLP018 Propagation de K7RA

    Spaceweather.com posted the following report on May 4:

    "REVERSED-POLARITY SUNSPOT EXPLODES: A rare reversed-polarity
    sunspot exploded today, producing a long-lasting M-class solar flare
    and a CME that might hit Earth. Geomagnetic storms are possible this
    weekend if/when the CME arrives."

    Sunspot activity and solar flux increased over the past reporting
    week, April 27 through May 3.

    Average daily sunspot numbers climbed from 91.4 to 114, while
    average daily solar flux grew from 139.4 to 151.5.

    Average daily planetary A index dropped from 26.9 to 13.6, and
    average daily middle latitude A index declined from 15.6 to 11.9.

    Predicted solar flux over the next month is 162 on May 5-6, 164 on
    May 7, 162 on May 8-9, 164 on May 10-11, 170 on May 12-13, then 165,
    160, 155, 150, 145 and 140 on May 14-19, 135 on May 20-21, then 130
    and 125 on May 22-23, 120 on May 24-25, then 125, 130 and 135 on May
    26-28, 140 on May 29 through June 2, then 145, 150 and 155, 160 and
    165 on June 3-7, 170 on June 8-9, then 165, 160, 155, 150, and 145
    on June 10-14. .

    Predicted planetary A index is 5 on May 5, then 12, 8, 5 and 5 on
    May 6-9, 5 on May 10-11, 8 on May 12, 5 on May 13-22, 12 and 20 on
    May 23-24, 15 on May 25-26, 8 and 12 on May 27-28, 10 on May 29-30,
    then 8, 5, 12 and 10 on May 31 through June 3, 5 on June 4-6, 8 on
    June 7-8, and 5 on June 9 through mid-month and beyond.

    On Wednesday, May 3 Spaceweather.com posted, "INTENSIFYING SOLAR
    ACTIVITY: Sunspot complex AR3293-3296 is crackling with strong
    M-class solar flares--six of them today so far."

    It looks like we face continued favorable HF propagation.

    Recently I wrote of my bafflement at 10 meter propagation I observed
    using FT8 and pskreporter.info, in which my signals were only being
    reported in Florida. I now have a better understanding of this.

    On May 1 from 1930-2030 UTC I saw the same thing, with reports from
    2,200-2,700 miles away, which suggests a 500 mile wide skip
    distance. Mexican stations also reported me, over that same distance
    in a 500 mile band. So, this suggests that it isn't just Florida,
    and that the same signal is stretching out into the Gulf of Mexico
    and the Atlantic Ocean, but I don't see it because there are no
    stations there to receive my signal.

    Later I saw multi-hop reports from ZL4KYH at 7,246 miles, 5W1SA at
    5,230 miles, LU8EX at 6,893 miles and LU4FTA at 6,750 miles.

    Jon N0JK wrote on April 29:

    "I was able to work LU9DO, LU8EX and PY2XB that afternoon. The South
    American signals popped up on what was otherwise a dead band. Later
    some station in Florida came in. I was running 50 watts and a 3
    element Yagi portable in EM28, northeast Kansas. May 1 - D2UY worked
    stations in Florida and W3LPL in Maryland on was likely Es -- TEP.

    "There will likely be more of these Es -- TEP openings in early
    May."

    Weekly Commentary on the Sun, the Magnetosphere, and the Earth's
    Ionosphere May 05-11, 2023 from OK1HH:

    "While long-term forecasters are beginning to come to terms with the possibility that the growth in solar activity could slow this year
    and the current 25th cycle may not be one of the high ones, solar
    activity has begun to increase. Already last week, sunspot group
    AR3288 in the southwest with an unstable delta class magnetic field
    was the source of an M7 class solar flare on May 1 at 1309 UTC. But
    another M7 class eruption occurred on May 3 in the newly emerged
    AR3293 in the northeastern part of the solar disk.

    "Interestingly, a new group of spots, AR3296 in the northwest,
    violates Hale's Law, as it has the opposite magnetic polarity that
    is appropriate in the current 11-year cycle (polarity should be
    negative on the left and positive on the right).

    "The solar wind speed and Earth's magnetic field activity have
    finally begun to decrease after a long active period, and the
    conditions for shortwave propagation have finally improved, although
    not to the extent we had hoped."

    A story from Sky & Telescope about the Sun:

    https://bit.ly/3NGlMbp

    Two stories about massive solar flares, one from about 400 years
    ago:

    https://bit.ly/427oI5w

    https://bit.ly/3ASEfu1

    Some nonsense about flares:

    https://bit.ly/3NGD5t3

    More Aurora in our future:

    https://bit.ly/3AZxDKl

    A story about Radio Blackout:

    https://bit.ly/41bVL74

    More about Aurora Australis:

    https://ab.co/44qDbet

    This weekend is the 10-10 CW QSO Party, on 10 meters of course:

    https://www.ten-ten.org/activity/2013-07-22-20-26-48/qso-party-rules

    Send your tips, reports, observations, questions and comments to
    k7ra@arrl.net. When reporting observations, don't forget to tell us
    which mode you were operating.

    For more information concerning shortwave radio propagation, see http://www.arrl.org/propagation and the ARRL Technical Information
    Service at http://arrl.org/propagation-of-rf-signals . For an
    explanation of numbers used in this bulletin, see http://arrl.org/the-sun-the-earth-the-ionosphere .

    An archive of past propagation bulletins is at http://arrl.org/w1aw-bulletins-archive-propagation . More good
    information and tutorials on propagation are at http://k9la.us/ .

    Instructions for starting or ending email distribution of ARRL
    bulletins are at http://arrl.org/bulletins .

    Sunspot numbers for April 27 through May 3, 2023 were 136, 111, 82,
    105, 87, 134, and 143, with a mean of 114. 10.7 cm flux was 140.8,
    149.8, 155.8, 153.5, 147.9, 156.8, and 156.2, with a mean of 151.5.
    Estimated planetary A indices were 23, 19, 20, 10, 10, 9, and 4,
    with a mean of 13.6. Middle latitude A index was 20, 16, 18, 8, 8,
    9, and 4, with a mean of 11.9.
    NNNN
    /EX
    --- SBBSecho 3.20-Win32
    * Origin: The Thunderbolt BBS - Little Rock, Arkansas (316:36/9)
  • From Daryl Stout@316:36/9 to All on Fri May 12 18:26:59 2023

    SB PROP @ ARL $ARLP019
    ARLP019 Propagation de K7RA

    ZCZC AP19
    QST de W1AW
    Propagation Forecast Bulletin 19 ARLP019
    From Tad Cook, K7RA
    Seattle, WA May 12, 2023
    To all radio amateurs

    SB PROP ARL ARLP019
    ARLP019 Propagation de K7RA

    We saw a modest increase in solar activity in this reporting week,
    May 4-10.

    Average daily sunspot numbers nudged up from 114 to 119.3, and
    average daily solar flux from 151.5 to 167.1

    Average daily planetary A index changed from 13.6 to 15.1, and
    average middle latitude A index remained the same, 11.9.

    Predicted solar flux is 160 on May 12-13, then 155, 150 and 150 on
    May 14-16, 145 on May 17-18, 155 on May 19-21, 150 on May 22, 145 on
    May 23-25, then 140 and 145 on May 26-27, 155 on May 29-30, 160 on
    May 31 through June 1, 155 on June 2-3, 160 on June 4-7, then 165,
    160, 150, 145 and 150 on June 8-12, and 155 on June 13-17.

    Predicted planetary A index is 30, 12 and 8 on May 12-14, 5 on May
    15-22, then 12 and 20 on May 23-24, 15 on May 25-26, 10 on May
    27-28, 8 on May 29, 5 on May 30 through June 1, then 16, 12, 16 and
    12 on June 2-5, 8 on June 6-8, and 5 on June 9- 18, then 12 and 20
    on June 19-20.

    Stormy space weather:

    https://www.space.com/sun-reverse-sunspot-auroras-supercharge

    BBC on viewing aurora:

    https://www.sciencefocus.com/news/northern-lights-may-2023-backward-sunspot/

    More:

    https://bit.ly/44Rruxk

    Jon, N0JK wrote on May 9:

    "Good 6 Meter Es, TEP May 7 FT8 from northeast Kansas.

    I worked CX2AQ and LU5FF from home with an attic dipole on FT8. This
    around 2115 UTC. Not strong, but solid contacts. I then set up
    portable.

    Worked CE2SV and CE3SX. CE3SX called me, also FT8. Had difficulty
    keeping yagi up due to gusty winds. On ON4KST Dale, CE2SV noted:

    00:11:46 N0JK Jon, A struggle on my side, wind blew antenna down
    several times and broke director. Duct tape to the rescue.

    00:11:07 N0JK Jon (CE2SV) Dale - Thank you for the contact.

    22:42:46 CE2SV Dale (N0JK) Finally Jon ... TU

    Gary, N0KQY observes there is a 'consistent time frame' for Es --
    TEP to South America from the Midwest. Best seems to be 2000-0000
    UTC."

    Weekly Commentary on the Sun, the Magnetosphere, and the Earth's
    Ionosphere May 12-18, 2023 from F.K. Janda, OK1HH.

    "The more vivid and complex solar activity is, the less predictable
    it is. The same is valid for its effects in the Earth's
    magnetosphere and ionosphere.

    This was particularly true of the solar flares of May 4 and 5, and
    also of the G2 class geomagnetic storm with auroras. The CMEs
    overlapping each other were difficult to separate.

    Another CME that struck the Earth on May 7 (1544 UTC) was expected
    but, contrary to predictions, did not cause a significant storm.
    Another Coronal Mass Ejection (CME) hit the Earth on May 9 at 2310
    UTC.

    Shortly before, AR3296 (with reversed magnetic polarity and thus
    violating Hale's law) released a double solar flare.

    The consequence was the Dellinger effect (a shortwave fade) up to 25
    MHz from 1900-2100 UTC. Another CME followed with a velocity of over
    1,000 km/s (2.24 million mph). Shock waves at its leading edge
    accelerated protons to nearly the speed of light, making them
    'relativistic particles', for which time passes more slowly. They
    can reach the Earth and affect the ionosphere.

    These lines are written on the afternoon of 11 May UTC, when the
    particles from the eruption of 9 May with a maximum at 1858 UTC are
    expected to arrive.

    Large AR3296 and AR3297 will set behind the northwestern edge of the
    solar disc in a few days. In the meantime, AR3301 and AR3302 emerged
    in the northeast.

    Helioseismological observations indicate another large sunspot group
    will follow them out. Therefore, the current variable nature of the
    evolution with numerous disturbances will continue."

    Five days ago from Dr. Tamitha Skov:

    https://youtu.be/E1lBqqWEa5Q

    Send your tips, reports, observations, questions and comments to
    k7ra@arrl.net. When reporting observations, don't forget to tell us
    which mode you were operating.

    For more information concerning shortwave radio propagation, see http://www.arrl.org/propagation and the ARRL Technical Information
    Service at http://arrl.org/propagation-of-rf-signals . For an
    explanation of numbers used in this bulletin, see http://arrl.org/the-sun-the-earth-the-ionosphere .

    An archive of past propagation bulletins is at http://arrl.org/w1aw-bulletins-archive-propagation . More good
    information and tutorials on propagation are at http://k9la.us/ .

    Instructions for starting or ending email distribution of ARRL
    bulletins are at http://arrl.org/bulletins .

    Sunspot numbers for May 4 through 10, 2023 were 139, 90, 99, 99,
    103, 151, and 154, with a mean of 119.3. 10.7 cm flux was 162,
    161.9, 151.8, 157.2, 171.9, 194.7, and 170.1, with a mean of 167.1.
    Estimated planetary A indices were 6, 5, 30, 9, 16, 14, and 26, with
    a mean of 15.1. Middle latitude A index was 7, 4, 21, 8, 13, 11, and
    19, with a mean of 11.9.
    NNNN
    /EX
    --- SBBSecho 3.20-Win32
    * Origin: The Thunderbolt BBS - Little Rock, Arkansas (316:36/9)
  • From Daryl Stout@316:36/9 to All on Fri May 19 14:20:15 2023

    SB PROP @ ARL $ARLP020
    ARLP020 Propagation de K7RA

    ZCZC AP20
    QST de W1AW
    Propagation Forecast Bulletin 20 ARLP020
    From Tad Cook, K7RA
    Seattle, WA May 19, 2023
    To all radio amateurs

    SB PROP ARL ARLP020
    ARLP020 Propagation de K7RA

    This reporting week, May 11-17, average daily sunspot number was
    nearly the same as last week, 118.6 compared to 119.3, only
    marginally lower.

    But average daily solar flux dropped from 167.8 to 143.2.

    Geomagnetic indicators were quieter, both planetary and middle
    latitude A index at 9.6. Last week the two numbers were 15.1 and
    11.9, respectively.

    What is the outlook for the next few weeks?

    10.7 cm solar flux is forecast to have a peak of 165 on June 8.

    The predicted numbers are 145 on May 19, 140 on May 20-21, 135 on
    May 22-24, 140 on May 25-26, 145 on May 27, 155 on May 28-30, 160 on
    May 31 and June 1, 155 on June 2-3, 160 on June 4-7, then 165, 160,
    150, 145, and 150 on June 8-12, then 155 on June 13-17, 150 on June
    18, 145 on June 19-21, 140 and 145 on June 22-23, and 155 on June
    24-26 then 160 on June 27-28.

    Predicted planetary A index is 5, 8, 12, 15 and 5 on May 19-23, 12
    on May 24-25, 15 on May 26, 10 on May 27-28, 8 on May 29, 5 on May
    30 through June 1, then 16, 12, 16 and 12 on June 2-5, 8 on June
    6-8, then 5 on June 9-18, 12 and 20 on June 19-20, 15 on June 21-22,
    10 on June 23-24, 8 on June 25, and 5 on June 26-28.

    These numbers are updated daily here:

    https://services.swpc.noaa.gov/text/45-day-ap-forecast.txt

    Thanks to reader David Moore for this:

    "How 1,000 undergraduates helped solve an enduring mystery about the
    Sun:

    "https://www.sciencedaily.com/releases/2023/05/230509122026.htm

    "For three years at the height of the COVID-19 pandemic, a group of
    students spent an estimated 56,000 hours analyzing the behavior of
    hundreds of solar flares. Their results could help astrophysicists
    understand how the Sun's corona reaches temperatures of millions of
    degrees Fahrenheit."

    Weekly Commentary on the Sun, the Magnetosphere, and the Earth's
    Ionosphere - May 18, 2023, from F.K. Janda, OK1HH.

    "On May 12, we expected a CME impact from the flare on the evening
    of May 9. It was indeed registered - at 0635 UTC the geomagnetic
    storm began. However, it was weaker than expected, of G1 class.

    "On 13 May at 1915 UTC, an unexpected CME impact followed for a
    change, which again triggered another G1 class geomagnetic storm.

    "On 16 May, we expected another smaller CME. The particle cloud has
    been slowly approaching Earth since the magnetic filament eruption
    in the southern hemisphere of the Sun on 12 May.

    "The next solar flare on May 16, with a maximum at 1643 UTC, was
    M9.6 class. It came from a sunspot group still hiding behind the
    southeastern limb of the Sun. In fact, it may have been an X flare,
    partially obscured by the solar horizon. Yet it caused the strong
    Dellinger effect (shortwave fade) over North America. After the
    sunspot group came out on the solar disk, we could observe it as AR
    3310. It's about three times wider than Earth, and its magnetic
    configuration promises more flares.

    "Not only was solar flare activity quite high, but the Sun was
    hurling so many CMEs into space that hardly a day went by without
    one hitting Earth. Therefore, the frequency of geomagnetic storms
    was also higher, followed by frequent deterioration of shortwave
    propagation conditions. In summary, the 25th solar cycle continues
    to evolve nicely."

    Frank, VO1HP sent this from St. Johns, Newfoundland:

    "On May 12 1957-2113 UTC, there was a strong 6M Es opening into mid
    South America. Logged 20 stations using FT8. No CW or SSB heard.
    Stations worked at VO1HP remote station: LU3CQ, CE3SX, 2SV, LI7DUE,
    9AEA, 9DO, 1FAM, 8EX, CX3VB, PP5BK, LU2DPW, CX1VH, PU3AMB, CX6VM,
    LU3FAP, XQ3SK, XQ3MCC, CE3VRT, 3SOC, and LU5FF.

    "Antenna 4el Yagi at 35ft overlooking ocean. K3 + PR6, KPA500
    KAT500. Other VO1s seen: VO1CH, VO1SIX, and VO1AW."

    On April 24, Rocky Riggs, W6RJK in Truckee, California wrote:

    "I was not very active until recently when I was introduced to POTA.
    The park I frequent the most would typically give me 40-60 contacts
    in a 2 hour period.

    "On Monday, April 24th, I went to the same park, and in 30+ minutes
    had no contacts and couldn't hear anyone either. I later found out
    that the solar storm was causing most of our radio problems. Until
    then, I had never considered much about solar flares, or how the Sun
    influences radio propagation. Now, finally, I'm trying to learn as
    much as I can. The K7RA Solar Update in the ARRL Newsletter is
    FANTASTIC and will be my source going forward to help me learn and
    understand.

    "Here's my question. Is there a 'real time' place where I can go to
    determine if a particular band has good propagation (I typically use
    20m and 40m)?

    "You know, like before I go out and get all set up and it's a 'goose
    egg.'"

    As I first reported in Propagation Forecast Bulletin ARLP017, I told
    him that a very useful tool (to use) is to check real time
    geomagnetic indices with this:

    https://www.swpc.noaa.gov/products/planetary-k-index

    Nice quiet conditions show a planetary A index at 1 or 2, unsettled
    conditions at 3, then above 3 conditions are disturbed. The scale is logarithmic, so each point in either direction is important.

    Another approach is to use pskreporter at https://www.pskreporter.info/pskmap.html which is handy if you live
    in a grid square that has many active hams, or a nearby grid that is
    more populated.

    You can check FT8 activity on any band. There is also a "Country of
    Callsign" selection so you can check activity across your nation of
    choice. Recently when I have raised nobody on 10 meter FT8 this
    option showed no activity here in the Pacific Northwest but plenty
    of 10 meter activity in the southeast United States.

    Here is a new video from Dr. Tamitha Skov, WX6SWW:

    https://youtu.be/xSQYjH6D_YA

    NASA sunspot picture:

    https://bit.ly/458DrPw

    A video of a recent eruption:

    https://www.youtube.com/watch?v=Rm7M5pqjCgY

    Here are articles about Radio Blackout:

    https://bit.ly/434c5bw

    https://bit.ly/3pWId2e

    https://bit.ly/45hXTxh

    https://bit.ly/3MEkCwa

    NASA warning of a Solar Storm threat:

    https://bit.ly/3pSK4p2

    Send your tips, reports, observations, questions and comments to
    k7ra@arrl.net. When reporting observations, don't forget to tell us
    which mode you were operating.

    For more information concerning shortwave radio propagation, see http://www.arrl.org/propagation and the ARRL Technical Information
    Service at http://arrl.org/propagation-of-rf-signals . For an
    explanation of numbers used in this bulletin, see http://arrl.org/the-sun-the-earth-the-ionosphere .

    An archive of past propagation bulletins is at http://arrl.org/w1aw-bulletins-archive-propagation . More good
    information and tutorials on propagation are at http://k9la.us/ .

    Instructions for starting or ending email distribution of ARRL
    bulletins are at http://arrl.org/bulletins .

    Sunspot numbers for May 11 through 17, 2023 were 152, 134, 120, 109,
    103, 106, and 106, with a mean of 118.6. 10.7 cm flux was 163.4,
    149.1, 143.8, 139.7, 134.5, 134.3, and 137.9, with a mean of 143.2.
    Estimated planetary A indices were 9, 19, 13, 8, 6, 8, and 4, with a
    mean of 9.6. Middle latitude A index was 10, 15, 12, 9, 6, 10, and
    5, with a mean of 9.6.
    NNNN
    /EX
    --- SBBSecho 3.20-Win32
    * Origin: The Thunderbolt BBS - Little Rock, Arkansas (316:36/9)
  • From Daryl Stout@316:36/9 to All on Fri May 26 20:18:57 2023

    SB PROP @ ARL $ARLP021
    ARLP021 Propagation de K7RA

    ZCZC AP21
    QST de W1AW
    Propagation Forecast Bulletin 21 ARLP021
    From Tad Cook, K7RA
    Seattle, WA May 26, 2023
    To all radio amateurs

    SB PROP ARL ARLP021
    ARLP021 Propagation de K7RA

    Both average daily sunspot numbers and solar flux increased this
    week. Average daily sunspot numbers rose from 118.6 to 133.4, while
    average solar flux went from 143.2 to 161.2.

    Geomagnetic indicators were more active. Average daily planetary A
    index went from 9.6 to 17.1, while average middle latitude A index
    rose from 9.6 to 14.4.

    Predicted solar flux is 150 on May 26, 155 on May 27 and 28, then
    150, 145, 140 and 135 on May 29 through June 1, 155 on June 2 to 4,
    then 160, 165, 160, 155, and 150 on June 5 to 9, 145 on June 10 and
    11, 150 on June 12, 155 on June 13 and 14, 160 on June 15, 165 on
    June 16 and 17, then 160, 155 and 150 on June 18 to 20, 155 on June
    21 and 22, then 160, 165 and 160 on June 23 to 25, 155 on June 26
    and 27, 150 on June 28, and 155 on June 29 to July 1, then 160, 165
    and 160 on July 2 to 4.

    Predicted planetary A index is 15, 8, 5, 12 and 10 on May 26 to 30,
    5 on May 31 through June 1, then 16, 8, 10 and 8 on June 2 to 5, 5
    on June 6 to 15, then 12, 10, 5, 18, 22, 15 and 10 on June 16 to 22,
    5 on June 23 to 28, then 16, 8, 10 and 8 on June 29 through July 2,
    and 5 through the first week of July.

    "Weekly Commentary on the Sun, the Magnetosphere, and the Earth's
    Ionosphere - May 25, 2023

    We've seen another seven days of turbulent developments on the Sun
    and around the Earth. The large, seen even without binoculars
    (e.g., eclipse glasses) visible sunspot group AR3310 in the southern
    hemisphere was the source of the strongest flare on May 16 with an
    X-ray event maximum of M9.6.

    Another group AR3311 in the north, due to its unstable magnetic
    field configuration "beta-gamma-delta", produced almost all the
    other flares. The stronger ones were the cause of Dellinger events
    (SWF = Shortwave fadeout, in the case of M9.6 it was registered in
    the whole shortwave range in the region where the Sun was high).
    Moreover, the eruptions, combined with sporadic E layer, often
    significantly affected the propagation in the lower shortwave bands
    by deep and irregular fadeouts.

    SOHO recorded a rare conjunction on May 21, when a filament near the
    Sun's north pole was ejected as a CME in direction to the Pleiades,
    Seven Sisters star cluster. Coronagraph on SOHO has been operating
    since 1995 and was the first to operate in real time. No one had
    ever seen anything like it before.

    Since May 24, we observed a new and rapidly growing group of spots,
    AR3315, in which we can expect more major solar flares as time goes
    on. So the turbulent evolution with changing and often worsening
    shortwave propagation conditions continues.

    F. K. Janda, A.R.S. OK1HH"

    K7EG wrote:

    "I have been in the DX hobby since 1950 and seem to see an
    increasing, alarming recent trend in solar and geomagnetic activity
    impacting trends in radio disturbances. Tell me I am wrong and it's
    just a 'blip' but solar activity seems beyond the norm and
    worsening."

    I replied that with greater solar activity we should expect more
    flares, solar wind, and disturbances. I think the disturbances are
    normal and expected with the rising solar cycle.

    When I suspect conditions are disturbed, this is where I check to
    see what is happening in real time:

    https://www.swpc.noaa.gov/products/planetary-k-index

    Beautiful aurora: https://tinyurl.com/2zxdmpu6

    Sunspot images: https://tinyurl.com/muaakxn9

    https://www.popsci.com/science/sun-images-powerful-solar-telescope/

    https://bit.ly/3MCqAwm

    Thanks to NO6ED for this story about an undersea volcano disrupting
    the ionosphere. https://bit.ly/428OAwM

    This weekend is the CQ World Wide WPX CW Contest. https://www.cqwpx.com/rules.htm

    Send your tips, reports, observations, questions and comments to
    k7ra@arrl.net. When reporting observations, don't forget to tell us
    which mode you were operating.

    For more information concerning shortwave radio propagation, see http://www.arrl.org/propagation and the ARRL Technical Information
    Service at http://arrl.org/propagation-of-rf-signals . For an
    explanation of numbers used in this bulletin, see http://arrl.org/the-sun-the-earth-the-ionosphere .

    An archive of past propagation bulletins is at http://arrl.org/w1aw-bulletins-archive-propagation . More good
    information and tutorials on propagation are at http://k9la.us/ .

    Instructions for starting or ending email distribution of ARRL
    bulletins are at http://arrl.org/bulletins .

    Sunspot numbers for May 18 through 24, 2023 were 121, 155, 138, 140,
    97, 130, and 153, with a mean of 133.4. 10.7 cm flux was 150.6,
    164.6, 169.6, 163.4, 161.5, 154.9, and 164.1, with a mean of 161.2.
    Estimated planetary A indices were 3, 9, 35, 28, 21, 12, and 12,
    with a mean of 17.1. Middle latitude A index was 8, 10, 26, 19, 17,
    11, and 10, with a mean of 14.4.
    NNNN
    /EX
    --- SBBSecho 3.20-Win32
    * Origin: The Thunderbolt BBS - Little Rock, Arkansas (316:36/9)
  • From Daryl Stout@316:36/9 to All on Fri Jun 2 16:03:45 2023

    SB PROP @ ARL $ARLP022
    ARLP022 Propagation de K7RA

    ZCZC AP22
    QST de W1AW
    Propagation Forecast Bulletin 22 ARLP022
    From Tad Cook, K7RA
    Seattle, WA June 2, 2023
    To all radio amateurs

    SB PROP ARL ARLP022
    ARLP022 Propagation de K7RA

    Average daily solar flux values dropped over the past week, but
    sunspot numbers were nearly the same, comparing May 25 to 31 to the
    previous week.

    Average daily solar flux declined from 161.2 to 155.3. Geomagnetic
    indicators were quieter, with average daily planetary A index
    declining from 17.1 to 7.3, and middle latitude numbers from 14.4 to
    7.9.

    Predicted solar flux is 160 on June 2, 155 on June 3-4, 150 on June
    5-8, 130 on June 9-11, then 135, 140, 143, 145, and 150 on June
    12-16, 155 on June 17-20, 150 on June 21-25, then 145, 140 and 135
    on June 26-28 and 130 on June 29 to July 8.

    Predicted planetary A index is 15, 12, 10 and 8 on June 2-5, 5 on
    June 6-17, then 22, 15, 12 and 10 on June 18-21, 5 on June 22-24, 12
    and 10 on June 25-26, then 5 on June 27-28, then 15, 12, 15, 10 and
    8 on June 29 through July 3, then 5 on July 4 through the middle of
    the month.

    Weekly Commentary on the Sun, the Magnetosphere, and the Earth's
    Ionosphere - June 1, 2023 from OK1HH.

    "The Sun still surprises us, it has been in the habit for billions
    of years, but we only observe it for a few hundred years. So, we
    have a right to be surprised by what it is doing and what we can
    observe with instruments on satellites and powerful solar telescopes
    on Earth, including the largest four-metre one on the island of Maui
    in Hawaii, which can see the very fine structures of sunspot nuclei.

    "What's more, we're seeing spots on the far side of the Sun that are
    so big, they affect the vibration of the whole Sun. But we can only
    see their structure and predict possible flares after they appear on
    the eastern limb of the solar disk, which was not at all the case
    with the current most active AR3315, which did not appear there. It
    emerged later, thereafter began to grow rapidly.

    "Conversely, the source of the next big flare was hidden behind the southeastern limb, and we only saw the prominence above it.

    "Meanwhile, the larger groups of sunspots have mostly moved to the
    western half of the solar disk. A large coronal hole in the southern
    hemisphere now crosses the central meridian. This increases the
    likelihood of geomagnetic disturbances starting on June 2."

    Mike, AK7ML wrote:

    "I recall in a movie about Pearl Harbor that they could not reach
    Hawaii from stateside on HF and then they sent the message by cable
    telegraph in routine status, so Pearl was not informed of the attack
    in time.

    "For years I have been able to work Australia in the morning and now
    it is Indonesia that is workable instead!"

    A story about a big sunspot:

    https://www.fox9.com/news/giant-sunspot-ar3310-visible-earth

    I've added information from this resource to the text appearing at
    the bottom of every propagation forecast bulletin (this resource
    comes from September 2002 QST):

    https://www.arrl.org/files/file/Technology/tis/info/pdf/0209038.pdf

    I was sad to learn that old friend Chip Margelli, K7JA became a
    Silent Key on May 25. Chip was from the Seattle area, and first came
    to my attention when he became proficient in the Japanese language
    during high school, then specialized in running JA stations at the
    old Rush Drake, W7RM contest station on Foulweather Bluff in Puget
    Sound. At one time he may have been the most famous American ham in
    Japan, or so I heard at the time.

    Send your tips, reports, observations, questions, and comments to k7ra@arrl.net. When reporting observations, don't forget to tell us
    which mode you were operating.

    For more information concerning shortwave radio propagation, see http://www.arrl.org/propagation and the ARRL Technical Information
    Service at http://arrl.org/propagation-of-rf-signals . For an
    explanation of numbers used in this bulletin, see http://arrl.org/the-sun-the-earth-the-ionosphere .

    An archive of past propagation bulletins is at http://arrl.org/w1aw-bulletins-archive-propagation . More good
    information and tutorials on propagation are at http://k9la.us/ .

    Instructions for starting or ending email distribution of ARRL
    bulletins are at http://arrl.org/bulletins .

    Sunspot numbers for May 25 through 31, 2023 were 121, 127, 125, 119,
    153, 144, and 147, with a mean of 133.7. 10.7 cm flux was 152.1,
    149, 156.9, 151.3, 154.4, 162, and 161.4, with a mean of 155.3.
    Estimated planetary A indices were 11, 6, 4, 11, 4, 5, and 10, with
    a mean of 7.3. Middle latitude A index was 11, 6, 5, 11, 5, 6, and
    11, with a mean of 7.9.
    NNNN
    /EX
    --- SBBSecho 3.20-Win32
    * Origin: The Thunderbolt BBS - Little Rock, Arkansas (316:36/9)
  • From Daryl Stout@316:36/9 to All on Fri Jun 9 14:14:37 2023

    SB PROP @ ARL $ARLP023
    ARLP023 Propagation de K7RA

    ZCZC AP23
    QST de W1AW
    Propagation Forecast Bulletin 23 ARLP023
    From Tad Cook, K7RA
    Seattle, WA June 9, 2023
    To all radio amateurs

    SB PROP ARL ARLP023
    ARLP023 Propagation de K7RA

    Solar activity was up this week, with the average daily sunspot
    number increasing from 133.7 to 139, and average daily solar flux
    from 155.3 to 166.8.

    Average daily planetary A index stayed the same at 7.3, and average
    middle latitude A index went from 7.9 to 8.6.

    Predicted solar flux doesn't show any improvement, with peaks at 170
    on June 23-25 and July 20-21.

    The forecast shows solar flux at 168, 163, 157, 160, 157, 153, 160
    and 150 on June 9-16, 155 on June 17-20, then 160 and 165 on June
    21-22, 170 on June 23-25, then 168, 165 and 162 on June 26-28, 160
    on June 29 through July 4, then 155, 150 and 145 on July 5-7, then
    140, 135, 140, 143, 145 and 150 on July 8-13, and 155 on July 14-17.

    Predicted planetary A index is 8, 5, 10 and 8 on June 9-12, 5 on
    June 13-17, then 22, 15, 12 and 10 on June 18-21, 5 on June 22-26,
    then 10, 12, 5 and 5 on June 27-30, then 8, 12 and 8 on July 1-3,
    and 5 on July 4-7, then 10, 12 and 8 on July 8-10, and 5 on July
    11-14, then 22. 15. 12 and 10 on July 15-18.

    In some previous bulletins I was reporting 10 meter propagation
    observed with FT8 only into Florida from my QTH in Seattle, and also
    into Mexico at a similar distance.

    Recently on 10 meters I am seeing propagation into VK/ZL, and in
    North America mostly into Southern California, Nevada, Utah and
    Arizona. Some seasonal variation, I suppose.

    Weekly Commentary on the Sun, the Magnetosphere, and the Earth's
    Ionosphere - June 8, 2023 from OK1HH:

    "In the last seven days, solar activity has remained at a slightly
    elevated level, with daily C-class flares and a few M-class flares.
    This, together with the decrease in geomagnetic activity, has
    resulted in a gradual increase in the daily maximum of the highest
    usable frequencies of the F2 ionospheric layer. At the same time,
    however, the attenuation in the lower ionospheric layers grew, which
    manifested as earlier morning closures and later evening openings of
    the longer shortwave bands.

    "Particle clouds from CMEs during solar flares mostly did not reach
    Earth - with one exception: on 7 June at 2224 UTC, the solar wind
    speed jumped from 340 to 380 km/s. For a short time, the Earth's
    magnetic field activity increased, usually only to K=3.

    "The situation was further complicated by the sporadic-E layer,
    whose season is approaching its peak.

    "Inhomogeneities (non-uniformities) in the sporadic-E layer appeared
    quite frequently and extended reflections were observed in the
    ionograms.

    "As a consequence, the scattering of electromagnetic waves was as
    well manifested as attenuation. We are talking about the ionosphere
    of the northern hemisphere of the Earth. Here we will wait for the
    improvement when Summer ends there - which fortunately will be much
    earlier than Summer ends in the troposphere."

    While searching for something else, I ran across this article from
    the RSGB:

    http://bit.ly/45TjWuA

    Mike, W9NY wrote:

    "Having lived through multiple sunspot cycles since I was first
    licensed in 1955, I cannot believe that 10 meters is nearly dead,
    and 15 meters is minimally open. Nothing on 6 meters either.

    "I discussed this with my cousin who is an astrophysicist at Oxford
    who basically said, 'there are a lot of factors.' I'm just wondering
    what our ham radio gurus think. I would have expected phenomenal
    propagation but there is very little. Might this be related to
    atomic/chemical changes in the Earth's ionosphere?"

    I offered the WA4TTK Solar Data Plotting Utility as a record of
    sunspot and solar flux data going back to 1989.

    It can be updated weekly with a plain text file of the latest
    propagation bulletin.

    The data file can then be imported to any spreadsheet program for
    analysis and custom graphing.

    http://www.craigcentral.com/sol.asp

    A new video from Dr. Tamitha Skov, WX6SWW:

    https://youtu.be/-ElKuld9xW8

    Send your tips, reports, observations, questions and comments to
    k7ra@arrl.net. When reporting observations, don't forget to tell us
    which mode you were operating.

    For more information concerning shortwave radio propagation, see http://www.arrl.org/propagation and the ARRL Technical Information
    Service at http://arrl.org/propagation-of-rf-signals . For an
    explanation of numbers used in this bulletin, see http://arrl.org/the-sun-the-earth-the-ionosphere .

    Also, check this article from September, 2002 QST:

    https://www.arrl.org/files/file/Technology/tis/info/pdf/0209038.pdf

    An archive of past propagation bulletins is at http://arrl.org/w1aw-bulletins-archive-propagation . More good
    information and tutorials on propagation are at http://k9la.us/ .

    Instructions for starting or ending email distribution of ARRL
    bulletins are at http://arrl.org/bulletins .

    Sunspot numbers for June 1 through 7, 2023 were 143, 147, 112, 110,
    151, 133, and 177, with a mean of 139. 10.7 cm flux was 163.9,
    162.3, 164.6, 168.3, 169.2, 171.8, and 167.2, with a mean of 166.8.
    Estimated planetary A indices were 13, 5, 5, 11, 5, 7, and 5, with a
    mean of 7.3. Middle latitude A index was 14, 8, 5, 11, 6, 10, and 6,
    with a mean of 8.6.
    NNNN
    /EX
    --- SBBSecho 3.20-Win32
    * Origin: The Thunderbolt BBS - Little Rock, Arkansas (316:36/9)
  • From Daryl Stout@316:36/9 to All on Fri Jun 16 09:47:58 2023

    SB PROP @ ARL $ARLP024
    ARLP024 Propagation de K7RA

    ZCZC AP24
    QST de W1AW
    Propagation Forecast Bulletin 24 ARLP024
    From Tad Cook, K7RA
    Seattle, WA June 16, 2023
    To all radio amateurs

    SB PROP ARL ARLP024
    ARLP024 Propagation de K7RA

    At 2256 UTC on June 16 the Australian Space Weather Forecast Centre
    issued a geomagnetic warning: "The solar wind speed on UT day 15-Jun
    has increased as the Earth entered a coronal hole wind stream after
    15/0545UT. Increased geomagnetic activity is expected for 16-Jun
    with isolated periods of G1-Minor level activity."

    Earlier in the day I checked the NOAA planetary K index page, and it
    showed a jump from K index of about 1.8 at 1200 UTC to about 4.1 at
    1500 and again at 1800 UTC, then about 4.5 at 2100 UTC and 5.5 at
    0000 UTC on June 16. At 0300 UTC it was down a bit to 5.

    See, https://www.swpc.noaa.gov/products/planetary-k-index .

    Solar activity declined this week, with average daily sunspot
    numbers dropping from 139 to 122, while average daily solar flux
    decreased from 166.8 to 154.8. This compares the current reporting
    week of June 8-14 against the previous seven days.

    Average daily planetary A index decreased from 7.3 to 5.7, and
    average daily middle latitude A index from 8.6 to 6.7.

    On June 14 Spaceweather.com reported two new sunspot groups emerging
    across the Sun's southeastern horizon.

    Forecasters Cundiff and Trost of the U.S. Air Force 557th Weather
    Wing predict solar flux at 155 on June 16-17, 160 on June 18-19,
    then 155, 160 and 165 on June 20-22, 170 on June 23-25, then 168,
    165 and 162 on June 26-28, 160 on June 29 through July 4, 165 on
    July 5, 170 on July 6-8, then 155, 157, 153 and 160 on July 9-12,
    150 on July 13-14, 155 on July 15-17, then 160 and 165 on July
    18-19, and 170 on July 20-22.

    Predicted planetary A index is 18, 12 and 8 on June 16-18, 5 on June
    19-20, 8 on June 21-22, 5 on June 23-26, 12 on June 27-28, 5 on June
    29-30, then 12 and 8 on July 1-2, 5 on July 3-7, 12 on July 8-10,
    then 5, 5, and 12 on July 11-13, and 10 on July 14-15, and 5 on July
    16-23.

    These predictions look great for ARRL Field Day, which is June
    24-25. Why? Solar flux peaks at 170 on June 23-25, and the predicted
    planetary A index is a nice quiet 5 on June 22-26. Next week we will
    present an updated forecast just prior to Field Day weekend.

    Weekly Commentary on the Sun, the Magnetosphere, and the Earth's
    Ionosphere June 16 - June 22, 2023 from F.K. Janda, OK1HH.

    "The first half of June was quieter than May, both on the Sun and in
    the Earth's magnetosphere and ionosphere.

    "However, helioseismic maps of the far side of the Sun showed a
    number of large active regions, probably sunspots. We therefore
    expected an increase in activity. But that's not likely to happen
    until a week from now.

    "Even so, there were some rather unexpected eruptions of moderate
    magnitude during the local midday, which triggered a SWF (Shortwave
    Fading) that could have broken the QSO in the longer half of the
    shortwave band.

    "Meanwhile, we observed a coronal hole in the solar equator region
    that crossed the central meridian on June 12.

    "Associated with it is the co-rotating interaction region (CIR),
    which are the transition zones between the slow and fast solar wind
    streams. Since the accumulation of solar plasma in the solar wind
    results in structures that are similar to the arrival of a CME, we
    expected a geomagnetic storm on the evening of 15 June UTC. The
    estimate was quite accurate - the disturbance began at 1500 UTC.

    "We can expect the geomagnetic field to be active for a few more
    days, including smaller storms."

    K6LMN wrote:

    "It was great on 6m last weekend. I was only on SSB on 6m, but I
    understand it was open all over on FT8. I believe the openings were
    caused by summer E-skip, not F2. I worked many, many stations in
    your grid square. Roger K6LMN in DM04sb Los Angeles."

    He sent this to N0JK:

    "We on the West Coast were finally treated to some decent E-skip on
    6 meters SSB and CW (do not know about FT8). The June VHF Contest
    was just great Saturday and Sunday afternoons into early evening,
    Pacific Daylight time. Before this contest the band out here has
    been fairly quiet.

    "So briefly, I was K6LMN/Limited Rover in DM03 DM04 all around LA.
    I had a tight schedule with many social engagements plus two
    funerals to attend. I could not get too serious with heavy artillery
    or going to 5,000+ ft. mountaintops. For 6m I simply used my Larsen
    5 ft. magmount on the car roof. The rig was my old IC-706IIG with
    only 90 watts SSB. I was also on 2m, 1-1/4m, and 70 cm.

    "Most DX contacts were on both days up to Oregon, Washington, Idaho,
    Montana, BC, and Alberta. But the surprise was Sunday early evening.
    Best 2 way DX was N9XG in EN60 (Indiana) and K9CT in EN50 (Illinois)
    with 1 hour to go before contest close. They were like 5 by 5 on
    peaks on SSB. I am sure all this big DX was double hop summer
    E-skip.

    "A surprise was VA6AN way up in Canada popping in/out on SSB with
    peaks up to 5 by 5 Sunday eve about 6:30 pm local time. However, the
    QRM was horrible (my whip is omnidirectional) so he did not work me.

    "I worked K7YO up in CN85 (his alternate QTH) and he said he was
    getting into Florida on SSB or CW or FT8 on 6M. Maybe triple hop
    E-skip?

    "I am unhappy that us West Coasters are not getting any F2 so far on
    6m in Solar Cycle 25. I am 85 years old, licensed in 1955 and was
    lucky to enjoy the all-time best F2 openings on 10m and 6m (AM) back
    in the Golden Days in 1956-1958 in Solar Cycle 19. Incredible!"

    N0JK sent a note on June 12 that he worked IK5YJY on 6 meter FT8. He
    also wrote: "6M Es all weekend and 2M Es Sunday eve for the ARRL VHF
    contest. By the way, you had a station (W9NY) comment about poor
    conditions on 6M in last week's bulletin. Last weekend was awesome.
    I made 3 JA contacts with 10w and a 3 el yagi from KS.

    "Today A71VV (Qatar) was in to Northeast KS around 1400z."

    Check out the images on the A71VV page on QRZ.com.

    Scotty, W7PSK sent a note on June 12 listing countries worked on 6
    meter FT8: Balearic Islands, France, Spain, England and Canada.

    An image of the International Space Station over a sunspot:

    https://bit.ly/3NgsByW

    A video too:

    https://bit.ly/43Em3B1

    A study of the Sun's coldest region:

    https://bit.ly/3X6ErQu

    More sunspots.

    https://bit.ly/3Nt5Ys6

    Another breathless warning from South Asia about flares:

    https://bit.ly/42Rt2FG

    This weekend is the 64th annual CW weekend of the All Asian DX
    Contest. See the JARL web site for rules:

    https://bit.ly/43GPrXq

    Send your tips, reports, observations, questions and comments to
    k7ra@arrl.net. When reporting observations, don't forget to tell us
    which mode you were operating.

    For more information concerning shortwave radio propagation, see http://www.arrl.org/propagation and the ARRL Technical Information
    Service at http://arrl.org/propagation-of-rf-signals . For an
    explanation of numbers used in this bulletin, see http://arrl.org/the-sun-the-earth-the-ionosphere .

    Also, check this article from September, 2002 QST:

    https://www.arrl.org/files/file/Technology/tis/info/pdf/0209038.pdf

    An archive of past propagation bulletins is at http://arrl.org/w1aw-bulletins-archive-propagation . More good
    information and tutorials on propagation are at http://k9la.us/

    Instructions for starting or ending email distribution of ARRL
    bulletins are at http://arrl.org/bulletins

    Sunspot numbers for June 8 through 14, 2023 were 149, 152, 116, 116,
    116, 98, and 107, with a mean of 122. 10.7 cm flux was 168.5, 164.3,
    161.2, 153.8, 146.1, 146.3, and 143.5, with a mean of 154.8.
    Estimated planetary A indices were 5, 4, 5, 9, 6, 6, and 5, with a
    mean of 5.7. Middle latitude A index was 6, 6, 4, 10, 8, 8, and 5,
    with a mean of 6.7.
    NNNN
    /EX
    --- SBBSecho 3.20-Win32
    * Origin: The Thunderbolt BBS - Little Rock, Arkansas (316:36/9)