The K7RA Solar Update
Tad Cook, K7RA, Seattle, reports: One new sunspot group appeared on December 4, but 4 days later it was gone. Average daily sunspot number declined from 46.1 to 24.6, and no sunspots were visible on December 8. Average daily solar flux went from 90.9 to 82.6.
Predicted solar flux over the next month does not seem promising. The December 8 forecast shows 78 and 80 on December 9 – 10; 82 on December 11 – 16; 85 on December 17 – 18; 87 on December 19 – 22; 86 on December 23 – 27; 84 on December 28; 82 on December 29 – January 2; 80 on January 3 – 5; 82 on January 6 – 8; 80 on January 9 – 10; 82 on January 11, and 85 on January 12 – 14.
Predicted planetary A index is 5, 10, 8, and 5 on December 9 – 12; 8 on December 13 – 14; 5 on December 15 – 16; 15, 12, 10, and 8 on December 17 – 20; 5 on December 21 – 26; 15, 18, and 12 on December 27 – 29; 8 on December 30 – January 3; 5 on January 4 – 5; 10, 8, 5, 12, and 10 on January 6 – 10; 5 on January 11 – 12, and 15, 12, 10, and 8 on January 13 – 16.
Sunspot numbers for December 2 – 8 were 45, 29, 35, 36, 14, 13, and 0, with a mean of 24.6. The 10.7-centimeter flux was 86.6, 85.3, 88.1, 82.7, 80, 78.9, and 76.9, with a mean of 82.6. Estimated planetary A indices were 10, 8, 9, 9, 7, 5, and 5, with a mean of 7.6. Middle latitude A index was 7, 4, 7, 6, 6, 3, and 4, with a mean of 5.3.
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