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Solar activity perked up this week. Average daily sunspot number
rose from 58.4 to 70.3, and solar flux averages increased from 113.3
to 129.9.
There are still problems with the Fredericksburg magnetometer, so I
used numbers from the Boulder, Colorado magnetometer for the middle
latitude A index.
At 2318 UTC on November 3, 2022 the Australian Space Weather
Forecasting Centre issued a geomagnetic disturbance warning:
"Increased geomagnetic activity expected due to coronal hole high
speed wind stream from November 4-5."
Planetary A index averages went from 19.4 to 13.7, and middle
latitude numbers changed from 9.1 to 14.3.
The solar flux prediction shows the highest values over the next
week, starting with 130 on November 4, then 135 on November 5-6,
then 130, 135, 130, and 125 on November 7-10, 115 on November 11-12,
112 on November 13-14, 110 on November 15, 108 on November 16-18,
104 on November 19, 100 on November 20-23, 98 on November 24-25,
then 100, 105, 105 and 110 on November 26-29, then 112 on November
30 through December 2, then 118 on December 3-6, 115 on December
7-9, and 112 on December 10-11.
Predicted planetary A index is 22. 30, 15, and 8 on November 4-7, 5
on November 8-10, then 18 and 15 on November 11-12, 5 on November
13-17, then 25, 15 and 8 on November 18-20, 5 on November 21-22,
then 8, 15 and 25 on November 23-25, 15 on November 26-27, then 18,
12, 10, 12, 20 and 15 on November 28 through December 3, then 5 on
December 4-6, 18 on December 7-8, 15 on December 9, and 5 on
December 10-14, and 25 on December 15.
F.K. Janda, OK1HH wrote:
"The evolution of solar activity, the Earth's magnetic field and the
state of the ionosphere in recent days has been varied, but not easy
to describe in a concise way (which is my aim).
"The reason for this is the variability of the evolution and the
absence of energetically significant phenomena.
"A week ago, there were five quiet sunspot groups on the Sun. None
of them posed a threat of strong flares. All had stable magnetic
fields that did not look like they would result in an eruption.
"Then, on the far side of the Sun, a sunspot appeared so large that
it changed the way the Sun vibrated.
"Helioseismic maps revealed its acoustic echo several days beyond
the Sun's northeastern edge. What mattered to us was that it was
about to appear at the northeastern limb of the Sun's disk.
"On October 26, we were delighted to see the Solar Dynamics
Observatory (SOD) satellite, which is in geostationary orbit,
studying the Sun's influence on planet Earth and the surrounding
universe.
"Most important for the forecast is the SDO/AIA image of coronal
holes, which may alert us to the possibility of an ionospheric
disturbance. We were cheered up by the fact that the Sun looks like
a jolly smiley face or a Halloween pumpkin, seen on
https://bit.ly/3fB1VvQ, just days before Halloween!
"A cheerful image, created by coronal holes in the Sun's atmosphere,
but mainly spewing a triple stream of solar wind toward Earth.
"Solar wind data from NOAA's DSCOVR spacecraft indicated that a
small, unexpected CME may have impacted Earth's magnetic field on
October 28 around 1400 UTC. A G1-class geomagnetic storm followed
after midnight UTC on October 29 after Earth entered the solar wind
stream flowing from the merry hole in the solar atmosphere.
"(The DSCOVR spacecraft is the Deep Space Climate Observatory. See
"Further, there were only four sunspots on the Sun, all of which had
stable magnetic fields that were unlikely to explode.
"Another flare took place on November 1 on the far side of the Sun.
The eruption hurled a CME into space. The blast site will flip to
the Earth side of the Sun in about a week.
"Watch for a larger coronal hole that has since moved to the Sun's
western hemisphere. Minor G1-class geomagnetic storms may result on
November 5, when a solar wind stream is expected to hit Earth's
magnetic field. Which will definitely affect shortwave propagation
conditions. Ideally, and with appropriate timing (daytime, ideally
afternoon), a significant improvement in the positive phase of the
disturbance could follow."
Oleh, KD7WPJ of San Diego, California reported: "On November 1st I
worked 3 Japanese stations on 10 m CW at 2238-2248 UTC from
Dictionary Hill (SOTA W6/SC-366) in San Diego, CA. I used 40 watts
and a homemade vertical with 4 radials."
Solar blasts in the news:
A Jack-o-Lantern Sun:
News about radio blackouts!
A smiley Sun:
New videos from Dr. Tamitha Skov, WX6SWW.
Part 3 of her mini-course:
This weekend is the ARRL CW Sweepstakes Contest, in which you work
domestic stations, and unlike ARRL Field Day, you do get multipliers
for sections worked. See https://www.arrl.org/sweepstakes for
details.
Send your tips, reports, observations, questions, and comments to
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
An archive of past propagation bulletins is at
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 October 27 through November 2, 2022 were 72, 87,
97, 68, 56, 63, and 49, with a mean of 70.3. 10.7 cm flux was 129.7,
129.3, 133.9, 130.5, 127.9, 128.1, and 129.7, with a mean of 129.9.
Estimated planetary A indices were 9, 16, 26, 12, 11, 8, and 14,
with a mean of 13.7. Middle latitude A index was 6, 15, 24, 14, 12,
6, and 11, with a mean of 12.6.
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