ARRL

ARRL Propagation Bulletin ARLP022 (2003)

SB PROP @ ARL $ARLP022
ARLP022 Propagation de K7RA

ZCZC AP22
QST de W1AW  
Propagation Forecast Bulletin 22  ARLP022
From Tad Cook, K7RA
Seattle, WA  May 30, 2003
To all radio amateurs 

SB PROP ARL ARLP022
ARLP022 Propagation de K7RA

Thanks so much to Carl Luetzelschwab, K9LA for writing last week's
propagation bulletin.  What a wonderful job he did.  If you missed
it, you can see it at http://www.arrl.org/w1aw/prop/.

While this bulletin is written early Friday UTC a severe geomagnetic
storm rages.  This is being written around 0600z on May 30, and for
the past three 3-hour reporting periods the planetary K index has
been 8, indicating extremely active conditions.  This is a shame,
because for some time now I've been hoping that the planetary A
index would drop below 10 around May 31, but the last day that
projection was shown at
http://sec.noaa.gov/ftpmenu/forecasts/45DF.html was May 26.  A late
forecast at 0359z on May 30 shows the projected planetary A index
for May 30 through June 2 as 60, 40, 25 and 20, followed by an A of
30 for June 3-5, 35 for June 6, and 30 again on June 7.

On May 29 earth was hit by two coronal mass ejections.  One was at
1215z and the other at 1900z.  A third coronal mass ejection may hit
us on Friday, May 30.  Rather than working HF, now seems a good time
for six-meter operations and observing aurora.  Solar flux over the
next few days (May 30 through June 2) is predicted at 145, 140, 135
and 125.  

Jim Tabor, KU5S has an interesting program called GeoAlert Wizard,
which he has just updated.  It sits in the system tray on your PC
and grabs solar and geophysical data automatically off the internet.
Check it out at www.taborsoft.com/gawiz.

For more information on propagation and an explanation of the
numbers used in this bulletin see the Propagation page on the ARRL
Web site at http://www.arrl.org/tis/info/propagation.html.  You can
write to the author of this bulletin at k7ra@arrl.net.

Sunspot numbers for May 22 through 28 were 110, 87, 84, 51, 65, 116,
and 116, with a mean of 89.9. 10.7 cm flux was 118.4, 117.9, 116.8,
121.1, 125.1, 128.8, and 130.2, with a mean of 122.6. Estimated
planetary A indices were 25, 21, 22, 22, 18, 26, and 36, with a mean
of 24.3.
NNNN
/EX