ARRL

ARRL Propagation Bulletin ARLP024 (1998)

SB PROP @ ARL $ARLP024
ARLP024 Propagation de K7VVV

ZCZC AP24
QST de W1AW
Propagation Forecast Bulletin 24  ARLP024
From Tad Cook, K7VVV
Seattle, WA  June 12, 1998
To all radio amateurs

SB PROP ARL ARLP024
ARLP024 Propagation de K7VVV

Solar activity was up again last week.  Average solar flux for
the previous 90 days rose one point to 110, and flux values were
above this level on every day, which indicates an upward trend.
Geomagnetic indices showed fairly unsettled conditions,
particularly on June 7 when planetary K indices went as high as
four and five.

The predicted solar flux for this weekend, Friday through Sunday,
is 115, 120 and 122, and the planetary A index is expected to be
10, 8 and 12.  Beyond that the solar flux is may peak for the short
term around 126 on June 16 or 17, then drop below 120 by June 20,
below 115 by June 24, and bottom out above 110 for June 26 through
July 6.  Somewhat unsettled geomagnetic conditions may appear again
June 19-21 and July 2-4.  Old region 8226 appeared to be growing as
it left the west limb of the sun near the end of May, and it could
produce some flares between June 12-25.

Dr. Dick Altrock of the USAF released a statement in conjunction
with the National Solar Observatory about the peak of this solar
cycle.  He is looking at long-term variation of solar emission
features that move toward the solar poles prior to solar cycle
maximum.  Since this emission feature already appeared over a year
ago at 55 degrees north latitude and is continuing to move toward
the poles, the solar maximum earlier believed to be slated for 2000
is now predicted for next year.

From VHF reports, GJ4ICD reports fantastic conditions on six
meters, and N7EIJ near Portland, Oregon reported working N7ML in
Montana on aurora and backscatter on the same band over the
weekend.  On the same date VE6XT in Calgary reported incredible
auroral E conditions on six with stations all across Canada and
Alaska.  Also on Saturday K2SPO in New York worked EH7KW (Spain) on
six.

N1BUG has a wonderful site on the web for monitoring auroras that
can be found on the web via a couple of URLs, including
http://www.mint.net/~n1bug/prop/aumon/aufr.html and also
http://www.qsl.net/n1bug/prop/aumon/aufr.html.

Sunspot Numbers for June 4 through June 10 were 92, 99, 110, 96,
104, 101 and 103 with a mean of 100.7.  10.7 cm flux was 111.7,
115, 115.1, 113, 116.9, 112.3 and 112.4, with a mean of 113.8, and
estimated planetary A indices were 12, 13, 14, 18, 12, 10, and 15,
with a mean of 13.4.
NNNN
/EX