• ARLP035 Propagation de K7RA

    From ARRL Web site@3:633/280.2 to All on Sat Sep 3 04:16:10 2022
    SB PROP @ ARL $ARLP035
    ARLP035 Propagation de K7RA

    ZCZC AP35
    QST de W1AW
    Propagation Forecast Bulletin 35 ARLP035
    From Tad Cook, K7RA
    Seattle, WA September 2, 2022
    To all radio amateurs

    SB PROP ARL ARLP035
    ARLP035 Propagation de K7RA

    The past week saw many interesting events. The DRAO observatory at
    Penticton, British Columbia (the source of 10.7 cm solar flux
    measurements) was overwhelmed by solar flares, and at 2000 UTC on
    August 28 reported a solar flux value of 251.9, and the next day at
    1700 UTC, a value of 357.1.

    The 2000 UTC local noon numbers are the official solar flux number
    for each day, so for the August 28 value I chose to report the 2300
    UTC number of 133.5 instead.

    I checked with astronomer Andrew Gray at Penticton, and he reported,
    "The high values are indeed because of solar activity, both
    yesterday and today flares occurred right during our flux
    measurements."

    Solar activity increased this reporting week (August 25-31) with
    average daily sunspot numbers rising from 58.7 to 74.9 and solar
    flux from 104.5 to 123.8.

    Without that correction for August 28, average daily solar flux
    would have been 140.8 instead of 123.8.

    I have seen these errors in the past, but they are rare. When they
    occur, there is only 1/3 chance they will happen during the daily
    2000 UTC reading, which sends them into the official daily solar
    flux data.

    Note that NOAA did not correct the high false value:

    https://services.swpc.noaa.gov/text/daily-solar-indices.txt

    Average daily A index was a little lower, the planetary values
    shifting from 12.6 to 10.1 and middle latitude from 11 to 9.4.

    Three new sunspot groups appeared on August 25 at the beginning of
    the reporting week, but none until September 1, with two new sunspot
    groups. The daily sunspot number rose from 42 on Wednesday to 67 on
    Thursday.

    Total sunspot area peaked on August 27.

    Predicted solar flux is more optimistic in the Thursday night
    version, as opposed to the Wednesday forecast reported in the ARRL
    Letter.

    Instead of 110 on September 2, the latest forecast is 116, 118 and
    118 on September 2-4, 115 on September 5, 110 on September 6-8, then
    118, 124, 130 and 128 on September 9-12, then 120, 117, 105 and 102
    on September 13-16, then 98 on September 17-18, then 104, 102 and
    108 on September 19-21, 118 on September 22-23, 124 and 125 on
    September 24-25, 120 on September 26-28, 115 on September 29 to
    October 1, then 112 on October 2, 108 on October 3-4, then 115, 120,
    124 and 130 on October 5-8.

    Flux values may briefly dip below 100 in mid-October.

    Predicted planetary A index is 10, 15, 30, 25 and 15 on September
    2-6, 10 on September 7-8, 12 and 8 on September 9-10, 5 on September
    11-12, then 12, 15 and 10 on September 13-15, 8 on September 16-17,
    5 on September 18-23, then 14, 10 and 8 on September 24-26, 5 on
    September 27-29, then 30, 38, 20, 15, 18, 10, 12 and 8 on September
    30 through October 7, and 5 on October 8-9.

    At 0209 UTC on September 2 the Australian Space Weather Forecasting
    Centre issued a geomagnetic disturbance warning: "Disturbed
    conditions caused by a high speed wind stream in a geoeffective
    direction are expected September 3-5."

    Frantislav K. Janda, OK1HH shares his weekly commentary:

    "The recent rise in solar activity, especially during August 27-30,
    was triggered by two sunspot groups, AR3088, which on 29 August fell
    behind the western limb of the solar disk, and AR3089, which on 30
    August passed through the central meridian, so entered the region of
    the so-called present active longitudes.

    "Both sunspot groups are in the southern hemisphere of the Sun,
    while in both were daily registered flares of moderate magnitude.
    CMEs have been registered in four cases. Given the proximity of the
    coronal hole, we would expect a significant increase in geomagnetic
    activity, but only at first approach.

    "However, there was only a slight increase in geomagnetic activity,
    confirming the current solar wind path models. We expect it to
    intensify and then increase in geomagnetic activity since about
    September 4 onwards. A further gradual increase in total solar
    activity can be expected a few days later."

    I (K7RA) noticed some curious 12 meter propagation, testing the band
    using FT8 on https://pskreporter.info/pskmap.html. This way I can
    see instantly where my signal is heard, and get accurate, objective
    signal reports.

    On August 31 at 2038-2116 UTC my calls were heard nowhere in North
    America outside my local area, which were stations 4-54 miles away.
    But all stations hearing me were in a straight line running through
    Mexico and Central America, then down to Brazil.

    XE1GLL, XE1EE, and XE1AQY, down to V31MA, LU6FL and PU3MSR. No 12
    meter resonant antenna, just a 32 foot end-fed indoor wire fed with
    a 4:1 UnUn transformer and automatic antenna tuner.

    Other curious 12 meter behavior was on Saturday, August 27 at 2252
    UTC when the only stations hearing me (FT8 again) were ZL2OK at
    7,120 miles with a strong signal report of +4 dB and WH6FXV at 2,649
    miles.

    Ten minutes later at 2302 UTC JA1QGI was the only station reporting,
    from 4,746 miles away. Four minutes later JN4MIV reported. At 2312
    UTC ZL2OK was back, this time reporting -4 dB, 8 dB lower than the
    earlier report.

    At 2315 UTC I worked JH6RKI and copied several more Japanese
    stations.

    Newsweek Magazine has been reporting interesting solar news
    recently:

    https://bit.ly/3q5XACl

    And Forbes.

    https://bit.ly/3AOWD6G

    Is "The Independent" one of the UK Fleet Street tabloids? Perhaps a
    RSGB member could inform us.

    https://bit.ly/3e5kJlF

    Another wonderful report from Dr. Tamitha Skov, WX6SWW, ham radio's
    own Space Weather Woman:

    https://youtu.be/hh_EPRjMmzY

    In the following links, many are presented for your amusement only.
    I do not believe that a huge solar flare will ever engulf the Earth.

    A canyon of fire: https://bit.ly/3RcWSiy

    EarthSky reports (page down): https://bit.ly/3wRStK1

    A report four weeks old, but still relevant: https://bit.ly/3KH0yH4

    Growing sunspot a threat: https://bit.ly/3cEgFZt

    Our angry Sun: https://bit.ly/3cHMiBm

    This one is a bit over the top: https://bit.ly/3TzEnqd

    From a few days ago: https://bit.ly/3CSJFY3

    Radio blackouts: https://bit.ly/3Rwwpwa

    Flares and blackouts: https://bit.ly/3KH2jEa

    More Flares: https://bit.ly/3e5ninN

    Existential threat: https://bit.ly/3Qc3MDE

    Flare facing Earth: https://bit.ly/3q5gzgv

    Sunspot somehow destroys Earth: https://bit.ly/3cHGSGy

    The 61st annual All Asian DX Phone contest is this weekend.
    Information can be found here: https://bit.ly/3ALPkwa

    Send your tips, reports, observations, questions, and comments to k7ra@arrl.net.

    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 August 25 through 31, 2022 were 94, 88, 84, 79,
    87, 50, and 42, with a mean of 74.9. 10.7 cm flux was 117.8, 118.6,
    127.5, 133.5, 130.6, 125.6, and 113.3, with a mean of 123.8.
    Estimated planetary A indices were 5, 5, 14, 7, 14, 13, and 13, with
    a mean of 10.1. Middle latitude A index was 5, 5, 11, 7, 13, 13, and
    12, with a mean of 9.4.
    NNNN
    /EX


    --- MBSE BBS v1.0.8 (Linux-x86_64)
    * Origin: American Radio Relay League (3:633/280.2@fidonet)
  • From ARRL Web site@3:633/280.2 to All on Sat Sep 2 09:07:43 2023
    SB PROP @ ARL $ARLP035
    ARLP035 Propagation de K7RA

    ZCZC AP35
    QST de W1AW
    Propagation Forecast Bulletin 35 ARLP035
    From Tad Cook, K7RA
    Seattle, WA September 1, 2023
    To all radio amateurs

    SB PROP ARL ARLP035
    ARLP035 Propagation de K7RA

    First, this alert from Australia.

    "ASWFC GEOMAGNETIC DISTURBANCE WARNING ISSUED AT 0706UTC/31 AUGUST
    2023 BY THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE.

    A filament eruption and associated coronal mass ejection (CME) were
    observed on UT day 30-Aug. This CME is expected to impact Earth from
    1800 UT +/- 12 hours on 02-Sep, with impacts possibly rolling into
    UT day 03-Sep. G1-G2 geomagnetic conditions are expected over this
    time, with a chance for periods of G3."

    Solar activity was down again this week, with average daily sunspot
    numbers dropping from 105.9 to 78.7, and average daily solar flux
    from 149.4 to 140.9.

    Only three sunspot groups appeared, one each on August 25, 28 and
    30.

    But I have noticed a gradual transition from summer toward fall
    conditions, with 10 and 12 meter openings more frequent. The
    autumnal equinox is only three weeks from now.

    Geomagnetic indicators were a little lower. Average planetary A
    index went from 8.4 to 7, and average middle latitude numbers from
    10.1 to 8.9.

    What is the outlook?

    Predicted solar flux shows a peak around 168 on September 18-21.

    Forecast values are 140 on September 1, then 150, 150 and 145 on
    September 2-4, 150 on September 5-9, 147 on September 10-11, then
    145, 150, 155, 150, 155 and 160 on September 12-17, 168 on September
    18-21, then 165, 160, and 148 on September 22-24, 150 on September
    25-26, then 152, 150, 145,and 140 on September 27-30, then 145 on
    October 1, 150 on October 2-3, 152 on October 4, 156 on October 5-6,
    150 on October 7. and 148 on October 8-9.

    Predicted planetary A index is 10, 12 and 35 on September 1-3, then
    15, 10 and 8 on September 4-6, 5 on September 7-13, then 12, 10, 10
    and 8 on September 14-17, 5 on September 18-22, then 10, 10 and 8 on
    September 23-25, 5 on September 26 to October 2, then 10, 8 and 8 on
    October 3-5, and 5 on October 6-10.

    Weekly Commentary on the Sun, the Magnetosphere, and the Earth's
    Ionosphere for September 1-7, 2023 from OK1HH.

    "On 27 August, we predicted a rise in geomagnetic activity,
    triggered by the arrival of particles from the filament solar flares
    three days earlier. It did occur, but to a lesser extent than we
    expected. No significant solar flare (at least of M-class) was
    observed until 25 August, which is somewhat surprising for the
    current phase of Cycle 25 development.

    We did not see a major flare until August 26 at 2250 UTC, and it was
    an M1-class solar flare, hidden behind the Sun's eastern edge, but
    it was a long duration eruption (LDE). It was accompanied by a CME,
    which of course was not heading toward Earth, but in this case Mars
    (which it should hit on September 1).

    The coronal mass ejection (CME) was observed on August 29 at about
    1748 UTC near the coordinates N05W35. Another major solar flare, C3,
    was observed on August 30 with a maximum at 2334 UTC at AR 3413.

    Prior to that, a filament of solar plasma disappeared near S18W24 at
    2015 UTC.

    Still, we expect only a slight increase in Earth's magnetic field
    activity in the next few days.

    Ionospheric propagation has varied erratically, with partial credit
    due to the sporadic E layer that occurred irregularly in Earth's
    northern hemisphere late this summer."

    India's solar mission: https://bit.ly/3PiPJ1N

    Flares: https://bit.ly/47X6gzC

    Four hours of Tamitha Skov and extreme space weather events:

    https://youtu.be/_Li9wxmmbQs

    This weekend is the phone portion of the All Asia DX Contest:

    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 August 24 through 30, 2023 were 86, 77, 75, 69,
    68, 82, and 94, with a mean of 78.7. 10.7 cm flux was 144.1, 138.9,
    139.3, 141.5, 141.7, 142.2, and 138.6, with a mean of 140.9.
    Estimated planetary A indices were 9, 5, 7, 11, 6, 5, and 6, with a
    mean of 7. Middle latitude A index was 9, 7, 9, 13, 8, 7, and 9,
    with a mean of 8.9.
    NNNN
    /EX


    --- MBSE BBS v1.0.8.4 (Linux-x86_64)
    * Origin: American Radio Relay League (3:633/280.2@fidonet)