[South Florida DX Association] ARLP047 Propagation de K7RA

[Bill Marx]

ZCZC AP47
> QST de W1AW  
> Propagation Forecast Bulletin 47  ARLP047
> From Tad Cook, K7RA
> Seattle, WA  November 11, 2005
> To all radio amateurs 
> 
> SB PROP ARL ARLP047
> ARLP047 Propagation de K7RA
> 
> We may be in another period of zero sunspots. From October 24-28
> there was a sunspot count of 0 on each day. Three days at the
> beginning of the month were no-sunspot days, and four months ago
> there were five days (July 18-22) with no spots. A year from now
> expect to see longer periods of 0 sunspot readings, possibly up to
> several weeks, based on what the periods between previous sunspot
> cycles were like.
> 
> Earlier this month Propagation Forecast Bulletin ARLP042 (October 6)
> referred to a nomograph, a graphic representation of numerical
> relations, like a ruler calibrated with inches and centimeters.
> This nomograph was supposed to illustrate the relationship between A
> index and K index, such as the figures seen in the table at,
> http://www.sec.noaa.gov/ftpdir/indices/DGD.txt. Unfortunately, the
> bulletin just quoted that same URL twice, but the unmentioned URL
> (the one with the nomograph) can be found at,
> http://www.ngdc.noaa.gov/stp/GEOMAG/kp_ap.html.
> 
> Geomagnetic conditions should be fairly active for Friday. The
> predicted planetary A index for Friday through Monday, November
> 11-14 is 15, 8, 5 and 5. The Prague Geophysical Institute predicts
> unsettled to active conditions on November 11 and 12, unsettled
> conditions on November 13, quiet to unsettled on November 14 and 15,
> and quiet conditions November 16-17.
> 
> Remember that for good HF propagation we want these geomagnetic
> numbers to be low, with sunspot numbers as high as possible.
> 
> If you would like to make a comment or have a tip for our readers,
> email the author at, k7ra at arrl.net.
> 
> For more information concerning radio propagation and an explanation
> of the numbers used in this bulletin see the ARRL Technical
> Information Service propagation page at,
> http://www.arrl.org/tis/info/propagation.html. An archive of past
> bulletins is found at, http://www.arrl.org/w1aw/prop/.
> 
> Sunspot numbers for November 3 through 9 were 24, 22, 18, 34, 31, 38
> and 13 with a mean of 25.7. 10.7 cm flux was 76.8, 77.4, 79.3, 81.7,
> 79.4, 79.4, and 78.1, with a mean of 78.9. Estimated planetary A
> indices were 24, 20, 10, 10, 6, 3 and 3 with a mean of 10.9.
> Estimated mid-latitude A indices were 19, 16, 10, 12, 6, 2 and 1,
> with a mean of 9.4.
> NNNN
> /EX
> 
>