[SFDXA] Propagation de K7RA

[William Marx]

> SB PROP @ ARL $ARLP009
> ARLP009 Propagation de K7RA
> 
> ZCZC AP09
> QST de W1AW
> Propagation Forecast Bulletin 9 ARLP009
> >From Tad Cook, K7RA
> Seattle, WA March 3, 2017
> To all radio amateurs
> 
> SB PROP ARL ARLP009
> ARLP009 Propagation de K7RA
> 
> On March 2 at 2353 UTC the Australian Space Forecast Centre issued a
> geomagnetic disturbance warning for March 3:
> 
> "The Earth is currently under the influence of a high speed solar
> wind stream from a recurrent coronal hole. On 3 March geomagnetic
> activity is expected to reach active levels. Isolated minor storm
> periods are also possible."
> 
> This reporting week (February 23 through March 1, 2017) sunspot and
> solar flux averages rose while geomagnetic indices remained about
> the same, compared to the previous seven days. Average daily sunspot
> numbers increased from 19.1 to 34.1, and average daily solar flux
> went from 78.5 to 81.3.
> 
> Average planetary A index barely changed from 11.3 to 13.1, and
> average mid-latitude A index (measured in Virginia) went from 9 to
> 8.7. The numbers went in opposite directions, but were each barely
> changed.
> 
> Predicted solar flux is 79 on March 3, 78 on March 4-5, 77 on March
> 6-7, 76 on March 8, 75 on March 9-14, then 74, 75, 77, 79, and 80 on
> March 15-19, 82 on March 20-23, 80 on March 24-25, 79 on March 26,
> 77 on March 27-28, 79 on March 29-31, 75 on April 1, 72 on April
> 2-3, 73 and 74 on April 4-5, 75 on April 6-10, and 74, 75 and 77 on
> April 11-13.
> 
> Predicted planetary A index is 22, 14, 10 and 8 on March 3-6, 5 on
> March 7-8, 8 on March 9, 5 on March 10-14 then 10, 20, 15, 10 and 8
> on March 15-19, then 5, 8, 10, 15, and 8 on March 20-24, 5 on March
> 25-26, then 12, 25, 20, 15 and 8 on March 27-31, 5 on April 1-10,
> and 10, 20, 15 and 10 on April 11-14.
> 
> F.K. Janda, OK1HH sent this forecast:
> 
> "Geomagnetic activity forecast for the period March 3-28, 2017
> 
> "Geomagnetic field will be:
> Quiet on March 8-9, 12, 14, 26
> Mostly quiet on March 10-11, 13, 15, 25
> Quiet to unsettled March 7, 20-22, 24
> Quiet to active on March 3-4, 6, 16, 18-19, 23, 27
> Active to disturbed on March 5, 17, 28
> 
> "Amplifications of the solar wind from coronal holes are expected on
> March 3-5, (6-8, 20-22,) 23-26.
> 
> "Remark: - Parenthesis means lower probability of activity
> enhancement and/or lower reliability of prediction."
> 
> We've been tracking a 3-month moving average of sunspot numbers for
> several years now. The peak was centered on February and March 2014,
> when the 3-month averages were 146.4 and 148.2. The average centered
> on the end of 2014 was 107.8, and a year later was 55.4. At the end
> of last year the average was 21, and the average centered on January
> 2017 was 20.6. The cycle will probably reach minimum in 2020.
> 
> Jon Jones, N0JK of Eastern Kansas sent this 10 meter update:
> 
> "The G2 class geomagnetic storm may have helped north - south paths.
> The TX5T Austral Islands DXpedition was loud on 28.027 MHz and in my
> log with one call at 2045z March 2. This on my mobile station. I saw
> aurora contacts spotted on 6 meters March 1 such as N8JX EN64 to
> K9MU EN44 at 2038z."
> 
> "Good conditions continued on 10 meters this week.  10 open to
> Pacific" - N4EK March 2, 2118z.
> 
> Dr. Tamitha Skov issued this solar storm forecast video on February
> 23:
> 
> http://bit.ly/2mNFO5g
> 
> This weekend is the ARRL International DX SSB Contest. See
> http://www.arrl.org/arrl-dx for details.
> 
> 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, see the ARRL
> Technical Information Service web page at,
> http://arrl.org/propagation-of-rf-signals. For an explanation of
> numbers used in this bulletin, see
> http://arrl.org/the-sun-the-earth-the-ionosphere.
> 
> An archive of past propagation bulletins is at
> http://arrl.org/w1aw-bulletins-archive-propagation. More good
> information and tutorials on propagation are at http://k9la.us/.
> 
> Monthly propagation charts between four USA regions and twelve
> overseas locations are at http://arrl.org/propagation. Instructions
> for starting or ending email distribution of ARRL bulletins are at
> http://arrl.org/bulletins.
> 
> Sunspot numbers for February 23 through March 1, 2017 were 18, 27,
> 25, 35, 40, 39, and 55, with a mean of 34.1. 10.7 cm flux was 83.3,
> 82.1, 80, 79, 82.2, 81.6, and 80.8, with a mean of 81.3. Estimated
> planetary A indices were 11, 20, 7, 2, 8, 8, and 36, with a mean of
> 13.1. Estimated mid-latitude A indices were 8, 15, 6, 0, 6, 5, and
> 21, with a mean of 8.7.
> NNNN
> /EX