The K7RA Solar Update
Tad Cook, K7RA, Seattle, reports: We saw a new sunspot on July 4, but it was from the declining Solar Cycle 24 and lasted only through the next day. Sunspot numbers were 12 and 11, for an average daily sunspot number of 3.3 for the week. Prior to July 4, no sunspots had been observed since June 15.
The average daily solar flux was 68.5; the previous week, it was 68.6. The average daily planetary A index inched up from 4.7 to 5.1, and the average daily middle latitude A index shifted from 4.7 to 6.4.
The 45-day outlook for solar flux does not look promising, with no values predicted at 70 or above. Predicted solar flux is 68 on July 9 – 24; 69 on July 25 – August 8; 68 on August 9 – 20, and 69 on August 21 – 22.
Predicted planetary A index is 8 on July 9; 5 on July 10 – 12; 8 on July 13; 5 on July 14 – 26; 8 on July 27 – 28; 5 on July 29 – 30; 12, 10, 8, and 8 on July 31 – August 3, and 5 on August 4 – 22.
Sunspot numbers for July 2 – 8 were 0, 0, 12, 11, 0, 0, and 0, with a mean of 3.3. The 10.7-centimeter flux was 68, 69.3, 69.5, 69.4, 68.5, 67.7, and 67.2, with a mean of 68.5. Estimated planetary A indices were 4, 4, 7, 10, 5, 4, and 2, with a mean of 5.1. Middle latitude A index was 5, 5, 9, 13, 6, 5, and 2, with a mean of 6.4.
A comprehensive K7RA Solar Update is posted Fridays on the ARRL website. For more information concerning radio propagation, visit the ARRL Technical Information Service, read "What the Numbers Mean…," and check out K9LA’s Propagation Page.
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