Tad Cook, K7RA, Seattle, reports: Solar activity was weak over the February 24 – March 2 reporting week with average daily sunspot numbers weakening from 54.3 to 44, but average daily solar flux rising slightly from 95.4 to 98.3.
Geomagnetic numbers were moderate. Average daily planetary A index declined from 9.6 to 7.3, and the middle latitude index from 7.3 to 5.6.
Predicted solar flux is 115 on March 3 – 4; 110 on March 5 – 6; 105 on March 7; 100 on March 8 – 10; 99 on March 11 – 13; 98 on March 14; 95 on March 15 – 16; 96, 97, 98, and 99 on March 17 – 20; 100 on March 21 – 22; 101 and 100 on March 23 – 24; 102 on March 25 – 26; 99 and 102 on March 27 – 28; 105 on March 29 – 31; 102 on April 1 – 2; 101 on April 3 – 4, and 100 on April 5 – 6.
Predicted planetary A index is 5, 8, 12, and 8 on March 3 – 6; 5 on March 7 – 10; 15, 12, 8, 5, and 8 on March 11 – 15; 5 on March 16 – 17; 10 on March 18; 15 on March 19 – 21; 7 on March 22 – 24; 5 and 10 on March 25 – 26; 12 on March 27 – 28; 8 on March 29 – 30; 12 on March 31; 15 on April 1 – 2, and 5 on April 3 – 6.
Sunspot numbers for February 24 – March 2 were 23, 22, 22, 48, 65, 62, and 66, with a mean of 44. The 10.7-centimeter flux was 92.3, 96.2, 96.5, 96.9, 99, 99.3, and 109.5, with a mean of 98.5. Estimated planetary A indices were 7, 8, 3, 13, 8, 8, and 4, with a mean of 7.3. Middle latitude A index was 6, 7, 1, 11, 5, 6, and 3, with a mean of 5.6.
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 the Propagation Page of Carl Luetzelschwab, K9LA.
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