ARRL

ARRL Propagation Bulletin ARLP028 (1996)

SB PROP @ ARL $ARLP028
ARLP028 Propagation de KT7H

ZCZC AP49
QST de W1AW
Propagation Forecast Bulletin 28  ARLP028
From Tad Cook, KT7H
Seattle, WA  July 12, 1996
To all radio amateurs

SB PROP ARL ARLP028
ARLP028 Propagation de KT7H

Is this a last gasp for Cycle 22?  Solar activity jumped
unexpectedly last week, with solar flux peaking at 83.6 on July 9,
and the average sunspot number up almost six points past the week
previous.

Solar flares around the first of the month produced slow moving
protons which affected the A and K index around July 3, 4 and 5.
The highest K index was 4.  Another flare this week is expected to
cause disturbed conditions on July 12 and 13, just in time for the
start of the IARU HF World Championship this weekend.

Look for the solar flux to get back down to around 70 by the middle
of the month, rising again above 70 after July 28.  The next solar
rotation will probably bring the current active region around again
to bump the solar flux up around 80 after August 1.

Sunspot Numbers for July 4 through 10 were 12, 12, 0, 27, 42, 44
and 36, with a mean of 24.7.  10.7 cm flux was 69.1, 68.6, 68.2,
71.9, 81.6, 83.6, and 79.8, with a mean of 74.7.

Here is a path projection for the teams in this weekend's World
Radiosport Championship, which are in the San Francisco Bay Area.

To Europe, 40 meters should be open around 0330z to 0500z, 20
meters should be best from 0600z to 0730z.  There is a small chance
of a 15 meter opening around 2130z.

To East Asia, check 80 meters from 1030z to 1330z, 40 meters from
0900z to 1400z, and 20 meters around 0400z to 1000z and again
around 1400z to 1630z.  There is a small chance that 15 meters will
be open from 2000z to 0800z.

To South Africa check 80 meters around 0400z, 40 meters around
0430z and 20 meters around 0530z to 0700z.

To the Caribbean check 80 meters from 0300z to 1030z and 40 meters
from 0130z to 1130z.  20 meters should be open around the clock,
with the worst times from 0730z to 1100z and 1400z to 1500z.

To the South Pacific 80 meters should be good from 0530z to 1330z,
40 meters from 0430z to 1430z and 20 meters from 0100z to 1100z.
Check 15 meters from 0100z to 0630z.

To South America check 80 meters from 0330z to 1030z, 40 meters
from 0230z to 1100z and 20 meters from 1200z to 1500z and 2230z to
0700z.  15 meters may open from 0100z to 0600z.
NNNN
/EX