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The K7RA Solar Update

Tad Cook, K7RA, Seattle, reports: A period of zero sunspots ran from February 4 – 17, but on Wednesday evening while viewing the STEREO spacecraft image, I saw a very bright area on our sun’s northeast horizon. Shortly after, Spaceweather.com reported, “A new active region is hiding just behind the sun’s northeastern limb. It might be a sunspot.”

The next day, February 18, two new sunspot regions appeared in our sun’s northern hemisphere, numbered 2802 and 2803. Region 2802 should soon rotate off the visible solar disc, and 2803 is the region just now crossing the eastern solar horizon.

Spaceweather.com warns us to expect a minor geomagnetic storm on February 21, triggered by a solar wind stream.

Average daily solar flux this week dropped from 72.8 to 72. Average daily planetary A index was unchanged from last week at 7.7.

Reported cracks in Earth’s magnetic field on Tuesday allowed solar wind to pour in, sparking aurora around the Arctic Circle. Alaska’s College A index jumped to 45 (A high number), after the K index hit seven at 0600 and 0900 UTC. This is from a single magnetometer near Fairbanks.

Predicted solar flux for the next 30 days is 71 on February 19 – 21; 70 on February 22 – 26; 73, 74, and, 73 on February 27 – March 1; 74 on March 2 – 3; 73 on March 4 – 6; 74, 70, and 74 on March 7 – 9; 76, 72, and 71 on March 10 – 12, and 72 on March 13 – 20. Flux values may rise to 76 again on March 23 – 24.

Predicted planetary A index is 5, 8, 18, 12, and 10 on February 19 – 23; 5 on February 24 – 28; 18, 15, and 8 on March 1 – 3; 5 on March 4 – 5; 15 on March 6; 5 on March 7 – 11; 18, 10, 8, and 8 on March 12 – 15; 5 on March 16 – 19; and 18, 15, and 12 on March 20 – 22.

Here’s the geomagnetic activity forecast for February – March 16 from F.K. Janda, OK1HH.

The geomagnetic field will be:

quiet on February 19, 25 – 27, March 5, 9 – 11, 14
quiet to unsettled on February 20, 24, March 4, 7 – 8, 13, 16
quiet to active on February 21, 23, 28, March 2 – 3, 12
unsettled to active February 22, March 1, (6, 15)
active to disturbed none predicted
Solar wind will intensify on February (21,) 22 – 24, (25,) March (1,) 2 – 4, (5 – 8, 12 – 15)

Parentheses mean lower probability of activity enhancement.

Predictability of changes remains low, as indicators are ambiguous.

Jeff Hartley, N8II, in West Virginia (FM19cj) sent this report last week:

“Sporadic E is slow to end for the winter season. On Sunday, February 7, we had Es to New England and to W/SW starting around 1915 UTC lasting until around 2145 UTC into Vermont. In the Vermont QSO Party, NS1DX, operating K2LE with big antennas, was S9 + 20 dB at one point around 2100 UTC on 15-meters SSB. I worked about seven Vermont QSOs total on 15 and added several on 20, which did not open from here until the Es. NX3A in Virginia, about 60 miles farther from Vermont, made five Vermont contacts on 10. I listened on 10, but there was nothing to Vermont when I checked.

F2 was definitely improved over a year ago into both Minnesota and British Columbia for their parties. On February 6, British Columbia was booming in to West Virginia the entire afternoon on 20, and there was an opening 1800 – 2000 UTC on 15 with good signals at the peak. Sunday was poorer, but still better than 2019 on 20.

Minnesota stations on 20 were loud most of the day on February 7 from 1445-2215 UTC.

Most days it is possible to work Europe on 15, but openings are short and most weak. MM5AJN/M near Aberdeen in northeast Scotland was about S-5 on 15 SSB on February 10 at 1415 UTC. Today, February 12, I worked a V51 in Namibia and TZ4AM (S-9) in Mali on 15 CW. Senegal was heard as well. I made one QSO with the Milan, Italy, area on 15 CW and a DJ5 in Stuttgart, Germany, on SSB.

Here’s the latest report from the Space Weather Woman, Tamitha Skov, WX6SWW, from a few days ago.

This weekend is the CW portion of the ARRL International DX Contest.

Sunspot numbers for February 11 – 17 were 0, 0, 0, 0, 0, 0, and 0, with a mean of 0. The 10.7-centimeter flux was 75.8, 72.1, 71.3, 71.4, 69.6, 71.5, and 72.4, with a mean of 72. Estimated planetary A indices were 4, 5, 13, 4, 5, 15, and 8, with a mean of 7.7. Middle latitude A index was 2, 4, 10, 3, 3, 11, and 6, with a mean of 5.6.

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

A propagation bulletin archive is available. For customizable propagation charts, visit the VOACAP Online for Ham Radio website.

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