SB PROP @ ARL $ARLP004
ARLP004 Propagation de K7RA

ZCZC AP04
QST de W1AW
Propagation Forecast Bulletin 4 ARLP004

From Tad Cook, K7RA

Seattle, WA January 26, 2024
To all radio amateurs

SB PROP ARL ARLP004
ARLP004 Propagation de K7RA

Just four new sunspot groups emerged this reporting week, January
18-24, one on each day, January 18-21.

But it looks like we may see flares, CMEs and geomagnetic storms
over the next few days. Spaceweather.com identified sunspot group
AR3561 as "hyperactive."

Sunspot numbers and solar flux declined, and geomagnetic indicators
rose, but only slightly.

Average daily sunspot number dropped from 167.3 to 130.6, and
average solar flux from 184.1 to 173.3.

Average planetary A index rose from 5 to 7.4, and middle latitude
numbers from 3.9 to 5.1.

Looking ahead, we may see a short term peak in solar flux centered
around February 11, and another about six weeks from now.

Predicted solar flux is 160 on January 26-27, 150 on January 28 to
February 1, 170 on February 2, 175 on February 3-4, 180 on February
5-8, then 190, 190 and 195 on February 9-11, then 190 and 185 on
February 12-13, 180 on February 14-15, then 175. 170, 175, 175, 170,
175, and 170 on February 16-22, then 165, 160, 165, 160 and 165 on
February 23-27, 170 on February 28-29, and 175 on March 1-2, then
180 on March 3-6.

Predicted planetary A index is 25, 30, 18, 10 and 8 on January
26-30, then 5 on January 31 through February 16, and 8 on February
17-18, then 5 on February 19-24, then 10, 12 and 10 on February
25-27, and 5 on February 28 through early March.

Weekly Commentary on the Sun, the Magnetosphere, and the Earth's
Ionosphere - January 25, 2024, from OK1HH:

"At the present stage of the 11-year solar cycle, there are five to
thirteen groups of spots (or active regions) on the Sun. In three of
them, we can observe such magnetic configuration that allows the
development of a larger flare, possibly with a CME.

"On the other hand, there are relatively few coronal holes on the
Sun, reducing the likelihood of Earth being hit by an enhanced solar
wind and then geomagnetic disturbances. Therefore, the evolution is
quieter, and the level of shortwave propagation is a little calmer
than we might otherwise expect."

Glenn Packard, K4ZOT reported from Atlanta, Georgia on January 22
that he worked New Zealand on 6 meter FT8 at 0257 UTC:

"I just happened to tune to 6M tonight after being disappointed on
6M for the Winter season. Then Bloom, ZL4TT, comes through at R-19
and me at -08. Just WOW. Called once and he came right back to me.
Band then went dead after the contact. Amateur Radio still has
surprised this Olde Man."

Solar Cycle 25 nearing its peak?

https://bit.ly/3Sv70GF

Articles about recent Solar activity:

https://bit.ly/4b6n48Z

https://bit.ly/3OiSL5r

https://bit.ly/3Ohoy6L

A NOAA article about Solar Cycle Progression:

https://www.swpc.noaa.gov/products/solar-cycle-progression

The latest report from Dr. Tamitha Skov, WX6SWW, for January 22:

https://youtu.be/41LGqYbxsvk

Did you know she has about 84,500 subscribers?

New, long program from Dr. Skov for January 25:

https://youtu.be/wQ7VFh_D2Mw

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 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/ .

Also, check this QST article about Solar Indices:

https://bit.ly/3Rc8Njt

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

Sunspot numbers for January 18 through 24 2024 were 113, 137, 144,
150, 139, 123, and 108, with a mean of 130.6. 10.7 cm flux was
162.3, 157.4, 166.3, 178.5, 196.1, 180.3, and 172, with a mean of
173.3. Estimated planetary A indices were 6, 8, 6, 6, 9, 7, and 10,
with a mean of 7.4. Middle latitude A index was 4, 5, 4, 5, 6, 5,
and 7, with a mean of 5.1.
NNNN
/EX


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

SB PROP @ ARL $ARLP004
ARLP004 Propagation Update

ZCZC AP04
QST de W1AW
Propagation Forecast Bulletin 4 ARLP004

From ARRL Headquarters

Newington CT February 7, 2025
To all radio amateurs

SB PROP ARL ARLP004
ARLP004 Propagation Update

Spaceweather.com reports that sunspot 3981 has produced more than 20
M-class solar flares, including two that almost reached category X.

The activity is likely to continue today. The sunspot retains a delta-class magnetic field that harbors energy for frequent explosions.


The current solar forecast calls for there to be no G1 (Minor) or greater geomagnetic storms. A potential glancing blow is possible on February 7 and
8.


Solar radiation - as observed by NOAA GOES-18 over the past 24 hours - was below the S-scale storm level thresholds. (The S-scale is used to indicate
the severity of energetic particles emitted from the Sun.) The scale ranges from S1 (minor) to S5 (extreme).


There is a chance for S1 (Minor) or greater solar radiation storms due to the complex cluster of sunspot groups in the Northwest Quadrant of the Sun.


Radio Blackouts are expected through February 8, with a chance for R3
(Strong) events due to several magnetically complex sunspot groups.


There is a chance for S1 (Minor) or greater solar radiation storms through February 9 as the complex cluster of sunspot regions in the north continues
to rotate closer to the western limb.


The geomagnetic field activity is expected to be unsettled to active levels
on February 10 to 19.


Weekly Commentary on the Sun, the Magnetosphere, and the Earth's Ionosphere, February 6, 2025, from F. K. Janda, OK1HH:


"The current 11-year solar cycle beautifully shows how little we still know about the universe we live in. Including the Sun, which is a relatively very stable star (otherwise we wouldn't be here). Each 'eleven year' cycle is different from all the previous ones,

and all previous attempts to predict the next one have always failed. Better said - some of them have proven to be valid. But only some.


"The current developments do not appear to be complex. Coronal holes 11 and
12 were followed by the somewhat surprisingly active regions of AR3976 -
3971, where eruptive activity rose and fell irregularly. Occasionally
including CMEs, which although they mostly did not hit the Earth, sometimes partially did.


"The ionospheric shortwave propagation conditions were therefore mostly above average, but at the same time very variable. There was no way to accurately predict their course, even if only for the next

24 hours. On the other hand, there was no major disturbance that would have made them significantly worse. There is only one thing to say about the
future development: it will be relatively easy to predict at first sight. But only at first sight, the reality will probably be more different than usual."


For more information concerning shortwave radio propagation, see www.arrl.org/propagation [ http://www.arrl.org/propagation?utm_source=Informz&utm_medium=Email&utm_campaign=ARRL
] and the ARRL Technical Information Service web page at arrl.org/propagation-of-rf-signals [
http://arrl.org/propagation-of-rf-signals ] .


For an explanation of numbers used in this bulletin, see arrl.org/the-sun-the-earth-the-ionosphere [ http://arrl.org/the-sun-the-earth-the-ionosphere ] .


An archive of past propagation bulletins is located at, arrl.org/w1aw-bulletins-archive-propagation [ http://arrl.org/w1aw-bulletins-archive-propagation ] .


Check out this QST article about Solar Indices:

https://bit.ly/3Rc8Njt [ https://bit.ly/3Rc8Njt ]

The predicted Planetary A index for the period February 9 to 14 is 5, 10, 15, 15, 20, and 10. The predicted largest Kp index is 2, 3, 3, 4, 5, and 3. Predicted 10.7 cm flux is 200, 200, 195, 195, 195, and 190.

NNNN
/EX

ARRL The National Association for Amateur Radio(R)
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--- MBSE BBS v1.0.8.4 (Linux-x86_64)
* Origin: American Radio Relay League (3:633/280.2@fidonet)