From the first week of this year, we saw a dramatic and welcome increase in solar activity, but it softened in this reporting week, January 19-25.
Average daily sunspot numbers starting with the final reporting week for 2022 were 96.1, 97, 135.9. 173.4 and 162.
Over the same period, average daily solar flux was 143.8, 157.8, 181.2, 221.8 and 198.9.
The northern hemisphere Winter Solstice was over a month ago, and through the next two months we will see a gradual transition toward Spring conditions.
Predicted solar flux over the next month shows values peaking near 205 on February 14-15, but flux values in the next few days are lower than those posted in Thursday's ARRL Letter.
Predicted numbers are 150 on January 27-28, 145 on January 29-30, 140 on January 31 through February 1, then 145, 150 and a big jump to 185 on February 2-4, 190 on February 5-6, 195 on February 7-12, 200 on February 13, 205 on February 14-15, 200 on February 16-18, then 195, 200, and 190 on February 19-21, 185 on February 22-23, 180 on February 24-25, then 175 on February 26 through March 1, then 180, 185 and 190 on March 2-4. Flux values are expected to keep rising, peaking above 200 again after March 10.
Predicted planetary A index, an indicator of geomagnetic instability is 8 on January 27-28, 5 on January 29 through February 1, 12 and 8 on February 2-3, 5 on February 4-6, 12 on February 7-8, then 15, 12 and 5 on February 9-11, 8 on February 12-13, 5 on February 14-17, then 8, 10, 10, 12 and 10 on February 18-22, 8 on February 23-25, then 5 on February 26-27, then 15, 10 and 8 on February 28 through March 2, and 5 on March 3-5, then 15 on March 6-8.
Weekly Commentary on the Sun, the Magnetosphere, and the Earth's Ionosphere - January 26, 2023 from F.K. Janda, OK1HH.
"We had a week of increased solar activity with areas of sunspots visible to the naked eye. These were AR3190 and AR3192. The ejected CMEs produced auroras at higher latitudes. Since the geomagnetic disturbances were mostly short-lived, they did not cause a noticeable deterioration in shortwave propagation.
"A CME hit the Earth on 17 January at around 2200 UTC. At the same time, it also hit the tail of comet ZTF (C/2022 E3) and broke it! A piece of the tail of comet ZTF was chipped off and then carried away by the solar wind.
"In recent days, AR3190 was the largest and most active, but even it produced no more than moderately powerful flares. Both large regions, AR3190 in the southwest and AR3192 in the northwest, are beyond the edge of the solar disk by January 26. This is associated with a significant drop in solar activity. While we know of other active regions beyond the eastern limb of the solar disk, these are not large enough to expect a repeat of the January pattern in February. But we expect a similarly erratic pattern contributing to limited forecasting capabilities."
Long time reader and contributor David Moore sends us this:
An article about Starspots:
KA3JAW is still having fun with 10 meter FM on 29.6 MHz.
On January 26 from 1430-1450 UTC he worked SV6EXH. With QSB, signals were 3x3 to 5x5. Earlier on January 21 at 1646 UTC he worked DM5TS, signals 4x5 with QSB.
Jon Jones, N0JK reported:
"Sunday morning (January 22, 2023) of the ARRL January VHF Contest had some great propagation on the 6 meter band. I operated portable signing W1AW/0 for VOTA. I was surprised when I turned on the radio after setting up and the FT8 band map screen was full of strong traces at 1505 UTC.
"There was a surprise sporadic-E opening Sunday morning to W1, W2, W3, VE3, and W8. The Ontario stations were booming in and I had a pileup calling. Even some F2 with PJ4MM in FK52 peaking at -8 dB at 1554 UTC.
"Even more amazing MM0AMW decoded several W9 stations on 6 meters. Several stations I worked, such as KW9A were spotted into Scotland. Unsure if the propagation mode was multi-hop Es or F2?
"Later that evening an Es -- TEP opening from the northeast states to South America."
More dramatic solar warnings.
Here is a prediction that was WAY off:
Space Weather Woman Dr. Tamitha Skov, WX6SWW, has a new video:
This weekend is the CQ World-Wide 160-Meter CW contest.
Check https://www.cq160.com for details.
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 January 19 through 25, 2023 were 166, 197, 194, 166, 144, 127, and 140, with a mean of 162. 10.7 cm flux was 226.1, 217.5, 208.7, 198.6, 189.1, 180.2, and 171.8, with a mean of 198.9. Estimated planetary A indices were 7, 6, 17, 9, 7, 4, and 7, with a mean of 8.1. Middle latitude A index was 6, 4, 11, 7, 5, 3, and 5, with a mean of 5.9.
댓글