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ARRL Propagation Bulletin ARLP050 (2002)

ARLP050 Propagation de K7VVV

QST de W1AW  
Propagation Forecast Bulletin 50  ARLP050
From Tad Cook, K7VVV
Seattle, WA  December 2, 2002
To all radio amateurs 

ARLP050 Propagation de K7VVV

This is a short after-holiday catch-up bulletin to bring us
up-to-date on solar flux, sunspot and planetary A index numbers.
These data couldn't be covered in last week's early bulletin.

From the previous week, mean daily sunspot numbers dropped over 24
points and daily solar flux was down nearly 37 points.  Average
planetary A index was about double, from 11.3 to 23.  The numbers
run through last Wednesday, and geomagnetic indices have continued
to run unsettled to active since then.  In four days we should have
an update for next weekend's ARRL 160 meter contest.  For that event
contesters will want quiet geomagnetic conditions and low A indices,
preferably in the low single digits.

Over the next few days solar flux is expected to rise from 155 on
Monday to 180 by the weekend.  Planetary A index is expected to
continue unsettled, with values of 20, 20 and 15 for Monday through

I ran across a Finnish web site devoted to photographs of aurora
borealis at
Don't miss paging through the gallery at  These are
some fantastic photos taken in Finland and Lapland over the past
couple of years.

Sunspot numbers for November 21 through 27 were 143, 124, 126, 123,
106, 100, and 112, with a mean of 119.1. 10.7 cm flux was 150.9,
149.1, 147.5, 146.2, 136.8, 142.3, and 142.6, with a mean of 145.1.
Estimated planetary A indices were 50, 24, 19, 16, 17, 14, and 21,
with a mean of 23.


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