SB PROP @ ARRL $ARLP044
ARLP044 Propagation DE KT7H
QST DE W1AW
Propagation Forecast Bulletin 44  ARLP044
>From Tad Cook, KT7H
Seattle, WA  October 28, 1994
To All Radio Amateurs
 
Solar flux was down slightly last week.  There was a disturbance
centered on October 23 when the A index was 41.  Conditions were
stable until October 22, and then the K index started climbing.
By the next day it had reached six, and conditions did not stabilize
until late on the 25th.
 
Solar flux should drop gradually until the first week in November,
then reach 90 again by mid month.  Unfortunately, poor conditions
are forecast for the DX contest this weekend, but the disturbance
may not occur until late in the contest on Sunday.  Poor conditions
should continue for the next few days.
 
Sunspot Numbers for October 20 through 26 were 75, 62, 55, 35, 37,
30 and 78, with a mean of 53.1.  10.7 cm flux was 90.1, 87.8, 85.5,
84.2, 82.2, 89.5 and 92.6, with a mean of 87.4.
 
Some correspondents have asked why the solar flux quoted in this
bulletin sometimes varies slightly from that given on WWV for the
same date.  An example is October 18 when we gave a solar flux of
90.5, but WWV reported 90 instead of rounding off to 91.  Since the
observatory in Penticton, BC reported 90.5 for that date, the only
obvious conclusion is that the Space Environment Service Center is
sometimes using funny rules for rounding numbers.  An example in
this report would be October 25 when Penticton reported 89.5, and
WWV reported 89 instead of 90.  Yet on October 22 when the flux was
85.5, WWV reported it as 86, which is the conventional
approximation.
 
The path projection for this week is for the center of the United
States to Central Europe during this weekend's DX contest.
 
80 meters looks good from 2300z to 0730z, and 40 meters from 2200z
to 0900z.  30 meters should be open from 1400z to 1600z and again
around 1900z and possibly 2100z.  20 meters should be good from
1500z to 1900z.  17 meters may be open some days around 1600 to
1700z.  15 meters and above does not look promising at this time,
although there is a chance of openings on 15 meters around the same
time as a 17 meter opening.
/EX