The K7RA Solar Update

Tad Cook, K7RA, Seattle, reports: Sunspots are gone, with none seen since February 3. Spaceweather.com reported on February 10 that a small proto-sunspot was struggling to form, but it was gone by the next day.

According to Spaceweather.com, 57% of the days so far in 2021 have been spotless. This is the same as the percentage of spotless days for all of 2020.

Average daily solar flux was 72.8 over the reporting week, with last week’s average at 74.2. Average planetary A index increased from 6.7 to 7.7, and average daily middle latitude A index rose from 4.6 to 6. These are still low, quiet numbers, quite favorable for conditions on 80 and 160 meters, especially during winter.

Predicted solar flux for the next 30 days is 75 on February 12 – 19; 78 on February 20 – 22; 76 on February 23 – 25; 74 on February 26; 73 on February 27 – March 1; 72 on March 2 – 7; 74 on March 8 – 10, and 76 on March 11 – 13.

Flux values may rise to 78 again after the middle of March, just before spring equinox in the Northern Hemisphere, which occurs on March 20.

Predicted planetary A index is 5 on February 12 – 14; 22 and 14 on February 15 – 16; 5 on February 17 – 20; 20, 16, and 12 on February 21 – 23; 5 on February 24 – 28, 18 and 14 on March 1 – 2; 5 on March 3 – 4; 8, 20, and 10 on March 5 – 7, and 5 on March 8 – 13.

Here’s the geomagnetic activity forecast for February 12 – March 9 from F.K. Janda, OK1HH.

The geomagnetic field will be:

• quiet on February 12, 18-19, 25-27, March 5, 8-9
• quiet to unsettled on February 13, 17, 24, March 3-4, 7
• quiet to active on February 14-16, 20, 23, 28, March 6
• unsettled to active February 21-22, March 1-2
• active to disturbed (none predicted)

Solar wind will intensify on February (15-17, 21-22,) 23-24, (25-26,) March 2-4

Parentheses mean lower probability of activity enhancement.

Predictability of changes remains low, as indications are ambiguous.

Thank you to Jon Jones, N0JK, for this info and an article in Eos on personal space weather stations and a network tying them together.

Jon, who is in Eastern Kansas (EM28), also reported a major 6-meter sporadic E opening across North America on February 7 – 8 UTC. First spotted around 1430 UTC, the Es continued until 0440 UTC.

From Kansas, Texas was coming in via Es around 1620 UTC. Later, XE2ML (DL74) and XE2JS (DL78) showed up at 2220 UTC.

“New Zealand was copied by stations in New England, and W5LDA (EM15) in Oklahoma was received by ZL1RS on three FT8 sequences,” Jon said.

Sunspot numbers for February 4 – 10 were 0, 0, 0, 0, 0, 0, and 0, with a mean of 0. The 10.7-centimeter flux was 73.9, 72.8, 72.5, 73.2, 73.6, 70, and 73.7, with a mean of 72.8. Estimated planetary A indices were 7, 6, 7, 21, 6, 4, and 3, with a mean of 7.7. Middle latitude A index was 7, 3, 4, 18, 6, 3, and 1, with a mean of 6.

For more information concerning radio propagation, visit the ARRL Technical Information Service, read “What the Numbers Mean…,” and check out K9LA’s Propagation Page.

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