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ARRL Propagation Bulletin ARLP003 (2022)

SB PROP @ ARL $ARLP003
ARLP003 Propagation de K7RA

ZCZC AP03
QST de W1AW  
Propagation Forecast Bulletin 3  ARLP003
From Tad Cook, K7RA
Seattle, WA  January 21, 2022
To all radio amateurs 

SB PROP ARL ARLP003
ARLP003 Propagation de K7RA

Solar and geomagnetic activity increased this week. Average daily
sunspot number was 52 points higher, rising from 42.4 to 94.4. The
sunspot number peaked at 120 last Saturday.

Average daily solar flux went from 101.6 to 112, peaking at 119.4 on
Sunday. Average daily planetary A index rose from 6.1 to 15.6, and
average middle latitude numbers went from 4.1 to 11.3. On January 20
the daily solar flux dipped to 99.3, the first daily noon reading
below 100 since January 6.

As reported by Spaceweather.com, Sunspot AR2929 erupted at 1744 UTC
on January 18 with an M1.5 class solar flare, blasting a pulse of
X-rays causing a shortwave radio blackout.

See https://bit.ly/3rC6W9t . Another eruption occurred on January
20, producing this blackout: https://bit.ly/3AfyLby .

I observed the January 18 blackout when I was using FT8 on 10 meters
to observe propagation using pskreporter.info. Just before the blast
I could see my 10 meter signal reported by stations on the East
Coast, and suddenly I saw no reports. The surprising part was during
that period no local stations reported copying my signal either.

Predicted solar flux is 95, 93 and 91 on January 21-23, 89 on
January 24-26, then 92 on January 27-28, 90 on January 29-30, 95 on
January 31, then 100 and 105 on February 1-2, 110 on February 3-10,
115 on February 11-14, then 110, 108 and 106 on February 15-17, 102
on February 18-21, 100 on February 22-23, 95 on February 24, and 90
on February 25-26. Flux values may rise to 110 after March 2.

Predicted planetary A index is 8, 10 and 12 on January 21-23, 8 on
January 24-26, 5 on January 27, 10 on January 28-30, 5 on January 31
through February 3, then 15 and 10 on February 4-5, 5 on February
6-9, then 12, 15, 12, 18 and 10 on February 10-14, 5 on February
15-19, 8 on February 20-22, 5 on February 23, and 10 on February
24-26, then back to 5 through the end of the month.

The predicted values summarized above are updated daily at:

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

Daily solar flux from Penticton, British Columbia:

https://bit.ly/33XlFnj

The local noon reading is the official SFN for the day.

Weekly Commentary on the Sun, the Magnetosphere, and the Earth's
Ionosphere-January 20, 2022, from F.K. Janda, OK1HH:

"We have been able to observe four to eight groups of sunspots on
the Sun over the past seven days. They are now mostly in the western
hemisphere, therefore solar flux has been declining.

"And suddenly a bang!

"This morning (January 20) we could observe a nice moderate-sized
solar flare near the northwestern limb of the solar disc. With a
maximum at 0601 UTC, it caused the Dellinger effect in the Indian
Ocean region for tens of minutes, followed by type II and IV solar
radio noise bursts, which confirmed the outburst of CME (but plasma
cloud likely will miss Earth).

"Now we are facing a gradual decline in solar activity. Larger
geomagnetic disturbances are expected in early February again. Their
more accurate prediction will depend on the further development of
the sunspot groups that are now located around the eastern limb of
the solar disk."

Here is a geomagnetic activity forecast for the period January
21-January 27, 2022:

"Quiet: Jan 22-23
Unsettled: Jan 21-22, 25-27
Active: Jan 24-25
Minor storm: Jan 24
Major storm: 0
Severe storm: 0

"Geomagnetic activity summary:

"After the last active and minor storm events (at the Budkov
observatory, minor storm event have been recorded at January 14, 16,
18 and 19) we expect geomagnetic activity decrease to unsettled
(January 21-22) or quiet to unsettled (January 22-23) level. Then,
starting at Monday, January 24, other active or minor storm events
are possible. At the end of current forecast period, we expect quiet
to unsettled conditions to return.

"Tomas Bayer
RWC Prague Institute of Geophysics of the ASCR, Prague
Department of Geomagnetism Budkov observatory (BDV)."
 
Interesting sunspot plot:

https://wwwbis.sidc.be/silso/eisnplot

KA3JAW in Easton, PA (FN20jq) reported:

"On Saturday, January 15, 2022 from 1346-1426 UTC started hearing
multiple central Mediterranean Sea stations, Italy, Greece, with
others along the Adriatic Sea on SSB mode on the 11 meter band.
Signal strengths deviated from fairly good to moderately strong with
moderate QSB. Average distances reached up to 4X sporadic-E ranges
at 4750 miles. This was the time frame when the Global D-Region
Absorption Predictions (D-RAP) maximum absorption attenuation
reached up to 16 MHz. For the rest of the day Es conditions were
dampened with higher amounts of sky wave background noise."

K7HBN (CN87) reported on January 14 via Western Washington DX Club:

"Today's opening on 28 MHz was unique indeed. The opening was
obviously enhanced by the solar wind stream from the coronal hole.
What was the strangest, I heard stations from Arizona with a strong
Au component on their signals calling CQ on the same frequency as
strong OH, SM and LA stations. I can't remember any such propagation
in my entire Ham Radio life, and I've orbited the Sun a few times."

Dr. Tamitha Skov, WX6SWW, reports, "Our Sun is getting busy":

https://youtu.be/2eXhwDHYeeY

If you would like to make a comment or have a tip for our readers,
please email the author at, k7ra@arrl.net.  

For more information concerning shortwave radio propagation, see
http://www.arrl.org/propagation and the ARRL Technical Information
Service web page 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 January 13 through 19, 2022 were 111, 112, 120,
103, 99, 59, and 57, with a mean of 94.4. 10.7 cm flux was 105.5,
110.2, 115.6, 119.4, 113.5, 114.5, and 105.3, with a mean of 112.
Estimated planetary A indices were 3, 15, 22, 19, 9, 18, and 23,
with a mean of 15.6. Middle latitude A index was 3, 10, 17, 16, 6,
12, and 15, with a mean of 11.3.
NNNN
/EX

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