ARLP009 Propagation de K7RA

QST de W1AW  
Propagation Forecast Bulletin 9  ARLP009
>From Tad Cook, K7RA
Seattle, WA  February 26, 2021
To all radio amateurs 

ARLP009 Propagation de K7RA

Sunspots have returned, and solar activity increased every day in
this reporting week. Thursday evening, reported
that in a single day, sunspot group AR2804 has doubled in size.

The total sunspot area was 200 millionths of a solar hemisphere, a
level not seen since the end of last year. It actually took two days
to double, Tuesday through Thursday covering 100, 150 and then 200.

Average daily sunspot number increased from 0 to 19.6, while average
daily solar flux rose from 72 to 75.7. Geomagnetic activity was also
higher, with average daily planetary A index increasing from 7.7 to
16, and average daily mid-latitude A index rose from 5.6 to 12.4.

Predicted solar flux for the next 30 days is 80 on February 26-28,
78 on March 1, 74 on March 2-5, 73 on March 5-6, then 74, 70, 74 and
76 on March 7-10, then 72, 71, 72 and 70 on March 11-14, then 71,
72, 71, 73, 76 and 75 on March 15-20, 72 on March 21-22, 76 on March
23-24, then 74 and 73 on March 25-26, then 74 and 73 again on March
Predicted planetary A index is 5 on February 26 through March 1,
then 18 and 12 on March 2-3, then 10, 8 and 15 on March 4-6, 5 on
March 7-11, then 15, 10 and 5 on March 12-14, then 15, 5, 8 and 18
on March 15-18, 20 on March 19-20, then 10 and 8 on March 21-22, and
5 on March 23-27.
Check this out, something called "Automated Solar Activity

While this looks interesting, so far I have been unable to download
any data more recent than 2009 or 2011.

Geomagnetic activity forecast for the period February 26 until March
23, 2021 from F.K. Janda, OK1HH and the Czech Propagation Interest
Group, compiling these geomagnetic activity weekly forecasts since
January 1978.
"Geomagnetic field will be
quiet on: March 9-10, 14
quiet to unsettled on: February 26-27, March 4-5, 13, 16-17, 20
quiet to active on: (February 28,) March 2-3, 7-8, 11, 15, 18-19, 21-23
unsettled to active: March (1,) 6, 12
active to disturbed: nothing expected
"Solar wind will intensify on: February 28, March 1-3, (4-9, 12,)
13, (14, 16-22).
"Parenthesis means lower probability of activity enhancement.
Predictability of changes remains low, as there are very ambiguous

Dr. Tamitha Skov, WX6SWW, posted this new video a few days ago:

Forbes magazine describes recent space weather as "spicy:"

Prediction from a few days back, with interesting graphics:

British tabloid describes a solar "Canyon Of Fire," but you need to
page through a lot of other stuff to read the whole article:

Ken Brown, N4SO (EM50tk) wrote on February 19:

"One measure of propagation is to call CQ at a very low power on CW
and look for returns on Reverse Beacon Network. This was done with
the K2 power control knob ALL the way down, and on an Elecraft W1
power meter reading 100 mW on the lowest scale. Several CQs were

"KD7YZ responded with a single spot. Location: GREENUP, KY (EM88ll).
QRPp  100 mW
Mode: CW
Band:  30m
Response from KD7YZ
Date and Time of test: 18 wpm 1747z 14 Feb"

This weekend is the CQ 160 Meter SSB Contest:

If you would like to make a comment or have a tip for our readers,
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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 18 through 24, 2021 were 12, 12, 12,
11, 26, 31, and 33, with a mean of 19.6. 10.7 cm flux was 71.1,
72.9, 76.4, 75.3, 75.9, 78.1, and 80.5, with a mean of 75.7.
Estimated planetary A indices were 5, 17, 20, 20, 17, 12, and 21,
with a mean of 16. Middle latitude A index was 2, 13, 15, 18, 13,
10, and 16, with a mean of 12.4.
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