QST de W1AW
Propagation Forecast Bulletin 24 ARLP024
From Tad Cook, K7VVV
Seattle, WA June 13, 1997
To all radio amateurs
SB PROP ARL ARLP024
ARLP024 Propagation de K7VVV
Solar activity is flat again, with solar flux headed into the low seventies. Flux values are expected to stay this way into the next month. There was an upset on June 9 when the planetary A index was 33 and the K index was as high as 6. This signaled greater absorption of radio waves, especially over polar paths.
NOAA had a recent report on the number of days with no sunspots for each month over the past four years. The values are in a bar graph, and there was a trend of more and more spotless days per month until October, 1996. The number of spotless days per month have been declining since then, a welcome sign for propagation watchers hoping for better conditions.
W6LX wrote to inquire about the comments of KE8YX in ARLP023 asking what he meant by the next solar cycle perhaps being a record cycle. I assume KE8YX meant that the next cycle could rival cycle 19 from the late 1950's in activity. That would be nice.
Sunspot Numbers for June 5 through 11 were 15, 15, 17, 36, 23, 11 and 11 with a mean of 18.3. 10.7 cm flux was 73.9, 74.2, 74.7, 73.2, 73.1, 71.9 and 70.8, with a mean of 73.1, and estimated planetary A indices were 3, 8, 11, 11, 33, 6, and 3, with a mean of 10.7.