ARLP044 Propagation de K7RA

 

SB PROP @ ARL $ARLP044

ARLP044 Propagation de K7RA

 

ZCZC AP44

QST de W1AW

Propagation Forecast Bulletin 44 ARLP044

From Tad Cook, K7RA

Seattle, WA November 15, 2024

To all radio amateurs

 

SB PROP ARL ARLP044

ARLP044 Propagation de K7RA

 

Only five new sunspot groups emerged this week. First was on November 7, next on November 9, two more on November 11, and another on November 13.

 

Average daily sunspot number declined from 193.4 to 141.6, while average daily solar flux went from 248.4 to 203.7.

 

Predicted solar flux is 145 on November 15-16, 155 on November 17-18, then 145 on November 19, 140 November 20-21, then 235, 240, 255 and 260 on November 22-25, 270 on November 26-27, then 255 and 250 on November 28-29, 240 on November 30 and December 1, 230 on December 2-3, and 225 and 220 on December 4-5, then 225 on December 6-7, and 175, 170, and 175 on December 8-10, then 165 on December 11-14, 178 and 185 on December 15-16, 200 on December 17-18, then 235, 240, 255 and 260 on December 19-22.

 

Estimated planetary A index is 12, 10, 8, 12 and 8 on November 15-19, 5 on November 20-24, 10 on November 25-26, then 8, 5, 5 and 10 on November 27-30, then 12, 9, 8, 7 and 5 on December 1-5, 12 on December 6-8, then 8, 12 and 10 on December 9-11, 8 on December 12-13, then 5, 8, 5 and 12 on December 14-17.

 

From HMI Science Nuggets, a possible explanation for solar cycle double peaks:

 

Weekly Commentary on the Sun, the Magnetosphere, and the Earth's Ionosphere - November 14, 2024, from F.K. Janda, OK1HH:

 

"Of the three active regions in the past few days, two have fallen behind the western limb of the solar disk. Therefore, the solar flux has dropped significantly. The third sunspot group was AR3889, which crossed the central meridian midweek. Its size of over 400 millionths of the solar disk area, and in particular the optical 'F' and magnetic 'Beta-Gamma-Delta' configurations, indicate that the production of moderate size flares will continue. So, because it is in the west, like most coronal holes, the solar wind should intensify, and the Earth's magnetic field activity should increase.

 

"This development, in fact, has already begun on November 14. First, conditions worsened after the polarity of the longitudinal component of the interplanetary magnetic field changed to negative between 0200-0500 UTC, while the density of protons in the solar wind increased. This was correctly followed by an increase in its velocity from 350 km/s to 440 km/s. Due to the anticipated increase in the solar wind, a further several days of turbulence is expected, followed by calming down only during the following week."

 

The latest report from Dr. Tamitha Skov, WX6SWW:

 

Send your tips, reports, observations, questions and comments to . When reporting observations, don't forget to tell us which mode you were operating.

 

For more information concerning shortwave radio propagation, see and the ARRL Technical Information Service web page at, . For an explanation of numbers used in this bulletin, see .

 

An archive of past propagation bulletins is at . More good information and tutorials on propagation are at .

 

Also, check this article: "Understanding Solar Indices" from September 2002 QST.

 

Instructions for starting or ending email subscriptions to ARRL bulletins are at .

 

Sunspot numbers for November 7 through 13, 2024 were 164, 167, 176, 121, 138, 116, and 109, with a mean of 141.6. 10.7 cm flux was 239.2, 231, 220.9, 230.6, 182.2, 171.7, and 150.3, with a mean of 203.7. Estimated planetary A indices were 9, 11, 32, 25, 10, 5, and 7, with a mean of 14.1. Middle latitude A Index was 7, 7, 24, 15, 7, 4, and 5, with a mean of 9.9.

NNNN

/EX

 


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