ARRL

ARRL Propagation Bulletin ARLP037 (2001)

SB PROP @ ARL $ARLP037
ARLP037 Propagation de K7VVV

ZCZC AP37
QST de W1AW  
Propagation Forecast Bulletin 37  ARLP037
From Tad Cook, K7VVV
Seattle, WA  September 7, 2001
To all radio amateurs 

SB PROP ARL ARLP037
ARLP037 Propagation de K7VVV

Compared to the previous seven days, average solar flux rose Nearly
ten points this week, but average sunspot numbers dropped about the
same amount.  There seems to be quite a bit of new activity
emerging.  Earth is exiting a solar wind, which brought planetary A
indices to 17 and 20 on Monday and Tuesday.  There were nine 3-hour
periods out of the two days which had a planetary K index of four.

A new sunspot group number 9608 is emerging on the southeastern limb
of the solar disk, and this could bring more flare activity and
coronal mass ejections.  The current outlook calls for solar flux to
rise over the next few days, to 225 on Friday, and around 230 on
Saturday through Tuesday.  This would be a big change, because flux
values have not been above this value since April 1.  This could be
an exiting fall DX season, and since solar activity will be 
declining, perhaps the best for years to come.

The current forecast shows a planetary A index around ten for the
next ten days, but of course this could change.

Shel Shallon has a new version 2.02 of W6ELprop, and you can
download it for free from http://www.qsl.net/w6elprop/.  The new
version has added some nice features, such as continuous scrolling
(the spreadsheet doesn't stop at 0000 UTC, but you can now scroll
backward and forward continuously).

Several people asked for path projections for the Worked All Europe
Phone Contest this weekend.  Since these are the same paths used for
a similar projection in ARLP033 on August 10, by comparing the two
you can see the effects of the change of season over the past month
as we move toward the fall equinox.  You can find old copies of this
bulletin on the ARRL web site.

The author's internet service provider closed its doors abruptly in
the final week of August, so the old email address has not worked
since then, even though it is not bouncing mail.  Best to use
k7vvv@arrl.net for correspondence.

Here are the path projections to Europe for this weekend.

From Philadelphia, 80 meters 2300-0600 UTC (best 0130-0400 UTC), 40
meters 2130-0730 UTC (best 0000-0430), 20 meters 1100-0230 UTC (best
2230-0100), 15 meters 1230-2300 UTC, 10 meters possibly 1630-2000
UTC.

From Atlanta, 80 meters 2330-0630 UTC, 40 meters 2230-0630 UTC (best
0030-0500), 20 meters 1900-0500 and 1030-1200 UTC, 15 meters
1200-2330 UTC, 10 meters 1800-2100 UTC.

From Dallas, 80 meters 0030-0500 UTC, 40 meters 0000-0630 UTC, 20
meters 2130-0100 and around 0600 UTC, 15 meters 1330-2200 UTC, 10
meters possibly 1700-2000 UTC.

From Cleveland, 80 meters 2330-0600 UTC, 40 meters 2200-0700 UTC, 20
meters 1130-0230 UTC, weakest 1330-1600 UTC, 15 meters 1300- 2300
UTC, 10 meters possibly 1300-2300 UTC.

From Omaha, 80 meters 0000-0600 UTC, 40 meters 2300-0630 UTC, 20
meters 1130-0530 UTC, weakest 1330-1700 UTC, 15 meters 1300-2300
UTC, 10 meters 1730-1930 UTC.

From Salt Lake City, 80 meters 0200-0530 UTC, 40 meters 0100-0630
UTC, 20 meters 2100-0030 UTC, 15 meters 1530-2130 UTC, 10 meters
possibly 1600-2200 UTC.

From California, 80 meters 0200-0530 UTC, 40 meters 0130-0630 UTC,
20 meters 2230-0220 and 0530-0730 UTC, 15 meters 1500-2130 UTC, 10
meters 1800-2000 UTC.

From Seattle, 80 meters 0230-0500 UTC, 40 meters 0130-0600 UTC, 20
meters 1400-0030 and 0530-0700 UTC, 15 meters 1630-2130 UTC 10
meters possibly 1600-2100 UTC.

From Alaska, 40 meters 2330-0630 UTC, 20 meters 0430-1200 and
1430-2330 UTC, 15 meters 1830-2100 UTC, 10 meters possibly 0600-
1030 or 1400-2300 UTC.

From Hawaii, 20 meters 0500-0930 and around 1530 UTC, 15 meters
0700-0930 and 1630-2100 UTC, 10 meters possibly around 1800 UTC.

Sunspot numbers for August 30 through September 5 were 138, 142,
153, 141, 168, 168 and 175 with a mean of 155. 10.7 cm flux was
199.2, 188.7, 184.1, 182.5, 198.7, 218.4 and 218.3, with a mean of
198.6, and estimated planetary A indices were 13, 16, 8, 7, 17, 20
and 10 with a mean of 13.
NNNN
/EX