ARRL PROPOGATION

SB PROP @ ARL $ARLP008
ARLP008 Propagation de K7RA

ZCZC AP08
QST de W1AW
Propagation Forecast Bulletin 8 ARLP008 From Tad Cook, K7RA Seattle, WA February 19, 2021 To all radio amateurs

SB PROP ARL ARLP008
ARLP008 Propagation de K7RA

A period of 0 sunspots ran from February 4-17, but Wednesday evening while viewing the STEREO spacecraft image at https://stereo.gsfc.nasa.gov 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.”

They called our attention to this image:

https://bit.ly/2NgREqr

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, then 73, 74, and 73 on February 27 through March 1, then 74 on March 2-3, 73 on March 4-6, then 74, 70 and 74 on March 7-9, then 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, then 18, 15 and 8 on March 1-3, 5 on March 4-5, 15 on March 6, 5 on March 7-11, then 18, 10, 8 and 8 on March 12-15, and 5 on March 16-19, then 18, 15 and 12 on March 20-22.

Geomagnetic activity forecast for the period February 19 to March 16, 2021 from F.K. Janda, OK1HH.

“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).

“- Parenthesis means 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 VT. In the VT QSO Party NS1DX operating K2LE with big antennas was S9+20dB at one point around 2100 UTC on 15M SSB. I worked about 7 VT QSOs total on 15M and added several on 20M which did not open from here until the Es. NX3A in VA about 60 miles farther from VT made 5 VT contacts on 10M. I listened on 10, nothing to VT when I checked.

“F2 was definitely improved over a year ago into both MN and BC for their parties. On the 6th, British Columbia was booming in to WV the entire afternoon on 20M 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.

“MN stations on 20 were loud most of the day on the 7th from 1445-2215 UTC.

“Most days it is possible to work EU on 15M, but openings are short and most weak. MM5AJN/m near Aberdeen in NE Scotland was about S5 on 15M SSB on the 10th at 1415 UTC. Today, the 12th, I worked a V51 in Namibia and TZ4AM in Mali was S9 on 15 CW; Senegal was heard as well. I made one QSO with the Milan, Italy area on 15 CW and a DJ5 station in Stuttgart, Germany on SSB.”

Dr. Tamitha Skov’s latest video from a few days ago:

This weekend is the CW portion of the ARRL International DX Contest. See https://contests.arrl.org/dxcw/ for rules.

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 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 February 11 through 17, 2021 were 0, 0, 0, 0, 0, 0, and 0, with a mean of 0. 10.7 cm 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.
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/EX

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