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ARRL Propagation Bulletin ARLP008 (2021)

ARLP008 Propagation de K7RA

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

ARLP008 Propagation de K7RA

A period of 0 sunspots ran from February 4-17, but Wednesday evening
while viewing the STEREO spacecraft image at I saw a very bright area on our Sun's
northeast horizon. Shortly after, 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:

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. 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

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

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

"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 for rules.

If you would like to make a comment or have a tip for our readers,
please email the author at, .
For more information concerning radio propagation, see and the ARRL Technical Information
Service web page at, For
an explanation of numbers used in this bulletin, see

An archive of past propagation bulletins is at More good
information and tutorials on propagation are at

Instructions for starting or ending email distribution of ARRL
bulletins are at .

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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