[South Florida DX Association] ARLP009 Propagation de K7RA

[Bill Marx]

> ZCZC AP09
> QST de W1AW  
> Propagation Forecast Bulletin 9  ARLP009
> From Tad Cook, K7RA
> Seattle, WA  March 4, 2005
> To all radio amateurs 
> 
> SB PROP ARL ARLP009
> ARLP009 Propagation de K7RA
> 
> This week saw a quiet sun, which will be a frequent observation over
> the next few years. The average daily sunspot number was down nearly
> 31 points to 14.9, and average daily solar flux was off 21 points to
> 76.3. Planetary geomagnetic activity was down just slightly, and mid
> latitude activity was just about the same as the previous week.
> 
> Unsettled to active geomagnetic conditions were expected over last
> weekend (February 26-27) due to a strong solar wind, but the only
> day with even slightly unsettled conditions was Monday, the last day
> of February, and any activity was brief. All week the Interplanetary
> Magnetic Field (IMF) pointed north, which shielded the earth from
> any solar wind. The sun was blank most of the week, with only small
> sunspot 739 transiting across the visible solar disk.
> 
> Check http://www.spaceweather.com/glossary/imf.html for a review of
> the IMF and how it can affect geomagnetic stability. Also check a
> site I haven't seen before,
> http://www.windows.ucar.edu/tour/link=/glossary/IMF.html&edu=high.
> This was submitted by Jon Jones, N0JK.
> 
> Over the next week expect a rising sunspot count and solar flux,
> with flux values peaking above 100 around March 11-14. March 6-9
> could see some unsettled to active geomagnetic conditions based on
> activity during the previous solar rotation.
> 
> This weekend is the ARRL International DX SSB Contest. Don't expect
> great conditions like when the sunspot cycle was higher, but at
> least we are moving toward the spring equinox and the geomagnetic
> conditions should be quiet.
> 
> Last week's bulletin stimulated a couple of questions about
> resources for understanding sporadic-E propagation. Go to the URL
> for the ARRL TIS propagation page mentioned a couple of paragraphs
> down, and check out the two-part "Sporadic-E - A Mystery Solved?"
> articles in PDF files. You will need an ARRL membership to log in to
> the web site to read this. There are other articles on other
> propagation topics on the same page that are available for anyone to
> read.
> 
> If you would like to comment or have a tip, email the author at,
> k7ra at arrl.net.
> 
> For more information concerning 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.
> 
> Sunspot numbers for February 24 through March 2 were 17, 15, 27, 12,
> 11, 11 and 11 with a mean of 14.9. 10.7 cm flux was 80.3, 78.2,
> 76.6, 75.8, 75, 73.7 and 74.6, with a mean of 76.3. Estimated
> planetary A indices were 5, 9, 9, 8, 12, 11 and 12 with a mean of
> 9.4. Estimated mid-latitude A indices were 4, 9, 9, 6, 8, 10 and 8,
> with a mean of 6.6.
> NNNN
> /EX
>