ARRL

ARRL Propagation Bulletin ARLP025 (1999)

SB PROP @ ARL $ARLP025
ARLP025 Propagation de K7VVV

ZCZC AP25
QST de W1AW  
Propagation Forecast Bulletin 25  ARLP025
From Tad Cook, K7VVV
Seattle, WA  June 18, 1999
To all radio amateurs 

SB PROP ARL ARLP025
ARLP025 Propagation de K7VVV

Average sunspot numbers were up ten points this week, and average
solar flux was down by just two points.  A peek at
http://www.wm7d.net/hamradio/solar/ shows how the two indices have
diverged a bit, with sunspot numbers climbing faster than solar
flux.

Solar flux is expected to bottom out at 150 on Friday, and then rise
over the weekend to 152 and 154.  Planetary A index is expected to
be 8, 12 and 10 over the same three days.  Solar flux should be back
to 160 by June 27, and stay around 165 June 28 through July 10.
This is based on the previous solar rotation, so we can always hope
for new activity to push the numbers higher.  But as we approach the
summer solstice, even higher solar flux won't make much difference
on 10 meters until the fall.

Geomagnetic indices look stable over the next few weeks, with
unsettled conditions around July 5.

In VHF news, last Friday WP4O had a nice opening to the Cayman
Islands and Africa on 6 meter SSB when he worked ZF1DC, EH8BPX and
CT3FT, all around 2000-2200 UTC.  On Wednesday of this week he
worked a pile of European stations on six.  N4VHF reported that on
Thursday he and a number of north Florida six meter stations all
worked CT3TF with good signals, and heard some weak EH8 stations.
No, this is not a typo on my part.  One station reported working
CT3FT and the other CT3TF.

Sunspot Numbers for June 10 through 16 were 214, 211, 233, 211, 210,
240 and 201 with a mean of 217.1.  10.7 cm flux was 161.1, 164.7,
168, 167.7, 168.2, 158.5 and 152.7, with a mean of 163, and
estimated planetary A indices were 7, 6, 7, 6, 4, 8 and 7, with a
mean of 6.4.

Path projections for this week are from Southern California.

To Europe, 40 meters 0300-0500 UTC, 30 meters 0200-0630 UTC, 20
meters 2330-1000 UTC, 17 meters all hours, strongest 0000-0530 UTC,
weakest 1830-2030 UTC, 15 meters possibly 2000-0200 UTC.

To Southern Africa, 80 meters 0300-0430 UTC, 40 meters 0230-0500
UTC, 30 meters 0200-0500 UTC, 20 meters 0030-0230 UTC and 0500-0700
UTC, 17 meters 2230-0130 UTC and 0530-0800 UTC, 15 meters 1930-0100
UTC and 0530-0730 UTC.

To the Caribbean, 80 meters 0230-1000 UTC, 40 meters 0100-1100 UTC,
30 meters 2330-1230 UTC (strongest 0330-0900 UTC), 20 meters all
hours, strongest 0330-0900 UTC, weakest 1700-1900 UTC, 17 meters all
hours, strongest 0230-1000 UTC, weakest 1700-1900 UTC, 15 meters
open most times, best 0300-0530 UTC, 12 meters possibly 1700-2230
UTC.

To South America, 80 meters 0230-1030 UTC, 40 meters 0200-1100 UTC,
30 meters 0100-1130 UTC, 20 meters 2230-1330 UTC (strongest
0300-1030 UTC), 17 meters all hours, best 0330-0800 UTC, weakest
1700-1900 UTC, 15 meters most hours, best 0100-0730 UTC, 12 meters
1430-0700 UTC, 10 meters 1730-2300 UTC, 0030-0130 UTC, and 0330-
0630 UTC.

To Australia, 80 meters 0700-1330 UTC, 40 meters 0630-1400 UTC, 30
meters 0530-1430 UTC, 20 meters 0400-1030 UTC, 17 meters 0130-0800
UTC, 15 meters 2030-0730 UTC, 12 meters 2100-0630 UTC, 10 meters
2130-0600 UTC.

To Japan, 80 meters 1000-1230 UTC, 40 meters 0930-1330 UTC, 30
meters 0830-1430 UTC, 20 meters 0530-1700 UTC, 17 meters all hours,
strongest 1000-1300 UTC, weakest 2130-0130 UTC.
NNNN
/EX