ARLP026 Propagation de K7VVV:
June 26, 1998

Propagation Forecast Bulletin 26 ARLP026
From Tad Cook, K7VVV
Seattle, WA June 26, 1998
To all radio amateurs

ARLP026 Propagation de K7VVV

Solar activity was lower again last week, and geomagnetic indices were unsettled. The average solar flux for the previous 90 days dropped one point from 108 to 107, and the solar flux for every day last week was lower than those figures. This is not a good indicator for an upward trend.

Over the next week the solar flux is expected to rise, reaching 115 from this weekend until the following July 4 weekend. The flux should go below 110 again around July 10.

On Friday through Sunday, June 26 through 28 the solar flux is forecast to be rising, at 110, 112 and 115. Over those same days look for unsettled conditions on Friday with a planetary A index around 15, and then an A index of 8 over the next two days. It looks like fairly good conditions for this Field Day weekend, with solar flux about 40 points higher than the 1997 Field Day.

Many readers of this bulletin use the WA4TTK Solar Data Plot Utility by Scott Craig. It grabs data out of this bulletin and stores it in a database, then plots the data for you. Users had problems grabbing the data from the past two bulletins due to some inadvertent changes in wording in ARLP024 and ARLP025. Scott has released version 3.03 which fixes this problem, and you can download it from Scott's homepage at

Here are some path projections for the Field Day weekend.

Don't forget to check 10 meters for some sporadic E skip.

Sunspot Numbers for June 18 through 24 were 68, 67, 80, 87, 64, 59 and 64 with a mean of 69.9. 10.7 cm flux was 100.1, 101.2, 101.1, 102, 100.5, 95.7 and 105.3, with a mean of 100.8, and estimated planetary A indices were 7, 14, 14, 15, 10, 10, and 14, with a mean of 12.