[SFDXA] Propagation de K7RA

[Bill]

SB PROP @ ARL $ARLP026
ARLP026 Propagation de K7RA

ZCZC AP26
QST de W1AW
Propagation Forecast Bulletin 26  ARLP026
>From Tad Cook, K7RA
Seattle, WA June 26, 2015
To all radio amateurs

SB PROP ARL ARLP026
ARLP026 Propagation de K7RA

This was a very active week for solar flares and aurora.On Monday 
andTuesdaythe planetary A index was 55 and 76, indicating a geomagnetic 
storm. The planetary A index was high again on Thursday, June 25 at 33, 
and the high latitude college A index was 42.

It turns out that the magnetometer at Fredericksburg, Virginia was 
knocked out on five of the seven days, so the mid-latitude A index we 
are reporting for June 18-21 and June 24 are approximations, or actually 
wild guesses based on other readings from magnetometers that were working.

Average daily sunspot numbers dropped from 99.9 during the week of June 
11-17 to 71.6 a week later. Average daily solar flux declined from 135.9 
to 130.8. Average daily planetary A index rose from 12.1 to 24.4.

The current outlook from NOAA/USAF has solar flux at 100 on June 26-27, 
105 on June 28, 110 on June 29, 115 on June 30, 120 on July 1, 125 on 
July 2-4, 120 on July 5-6, 125 on July 7-10, 130 on July 11-20, 125 
onJuly 21-22and 130 onJuly 23-24.

Predicted planetary A index is 15 and 45 onJune 26-27, then 60, 18 and 8 
onJune 28-30, 5 onJuly 1-4, then 25, 15 and 12 onJuly 5-7, then 10, 5 
and 8 onJuly 8-10, 18, 12 and 8 onJuly 11-13, 5 on July 14-17, 8 onJuly 
18-19, 5 onJuly 20-31, then 25, 15, 12 and 10 on August 1-4.

Petr Kolman, OK1MGW believes the geomagnetic field will be quiet to 
active onJune 26-27, mostly quietJune 28-30, quietJuly 1-2, quiet to 
unsettledJuly 3, active to disturbedJuly 4, quiet to active July 5, 
quiet to unsettledJuly 6-8, mostly quietJuly 9-10, quiet to activeJuly 
11-12, quiet to unsettledJuly 13-14, mostly quiet July 15-17, quiet to 
unsettledJuly 18, and quiet to active July 19-22.

Rich Zwirko, K1HTV reported on June 21: "Here in the Mid-Atlantic at the 
K1HTV Amissville, VA QTH, the Magic Band came alive just before 1600Z on 
Father's Day, June 21. The first of 13 countries that I worked were all 
from a southerly direction.  NP3CW was first in the log, followed by 
Yuri, UT1FG/MM in EL59 off the Cuban coast, CO3JA, 6Y5WJ, YV4NN and 
XE2CQ in DM12 northwestern Mexico.

"From 1650Z to 1750Z I worked 17 stations in W6 and W7 land. During that 
same hour, stations from GA and FL to as far west as NM and XE2 were 
working into HA, S5, YT, IS0, 9A and DL, but all I heard to the east 
during that hour was F2DX calling XE2X.

"It wasn't until 1845Z that I heard European DX here. In the next 65 
minutes I worked I0JX, IK5MEJ, IZ5BRW and IK5PWJ, HA8CE, ON7BG, OK1DO, 
G4DBL, S59A, HA8FK, PA2M and ON4IQ.  That was it for DX to the east for 
the day.

"Local late afternoon to early evening produced many more double hop 
QSOs to the West Coast, 15 stations in AZ, 15 in CA, 3 in NM and 1 in NV.

"It was a memorable Father's Day."

Jon Jones, N0JK wrote: "I worked Father's Day, but got off a little 
early at 2100Z and worked WU1ITU on 6 meters before going home.

"Sundayevening I worked 6Y5WJ from home for a 'new one' on 6 so all in 
all not a bad day.

"I have a shoe box full of 6 meter JA cards."

Rich Zwirko, K1HTV wrote again: "After the excellent double hop 6 meter 
Es earlier in the June 22 UTC day, the 6 meter and 2 meter bands came 
alive with aurora propagation around 1940Z. After making a few 6 meter 
AU QSOs from my FM18ap Virginia QTH to W1 and W2 land I switched to 144 
MHz at 1945Z. I quickly worked K9CT in IL (EN50), W9EWZ in WI (EN52), 
WB8AIZ in MI (EN82) on 2 meters as well as a couple of closer stations 
before the buzz mode switched off. On June 23, 6 meters was alive with 
Es propagation when I got on around 0100Z. I worked dozens of stations 
in the Midwestern States via Es until around 0340Z, when the aurora 
returned. It only lasted for about 30 minutes. I worked a few VE3s on 6 
meters before switching to 2 meters to work stations in Maine, PA and Ohio.

"Later that same UTC day (June 23) the 6 meter band was alive with 
single and double hop E-skip propagation. From 2130Z until the end of 
the UTC day, I worked what seemed to be an endless stream of over 120 
stations, with over three dozen from W6 and W7 land.

Shortly after 0000Z on June 24, while watching theDXMAPS.COM 
<http://dxmaps.com/>web site, it indicated that a patch of ionization, 
with an MUF in excess of 150 MHz, was well positioned for possible 2M 
propagation. It appeared to favor an area to the southwest of my FM18 VA 
QTH around 1000 to 1100 miles away. At 0006Z, W5VQ in EM13 (TX) answered 
my 2 meter SSB CQ. At 0028Z I called and worked K7XC in EM12, also in 
Texas, on CW, then again a few minutes later on SSB. Both Texas stations 
were around 1100 miles away. At 0028Z I was called on SSB by N5NET in 
EM26 in Oklahoma. I also heard but didn't work Sam, K5SW in EM25. About 
15 minutes later the same patch apparently was responsible for a QSO 
between W0LD operating temporarily in FM05or (NC) and K5PHF in DM61ts 
(TX), a distance of 1550 miles.

"The evening produced a number of ionized patches in the center of the 
country and others farther west, making for many hours of exciting VHF 
propagation."

Elwood Downey, WB0OEW wrote to Ken Tapping of the Penticton observatory 
in British Columbia (the source of 10.7 cm solar flux data) onJune 28, 
and Cc'd us: "Hello Ken, Do you expect today's spike in solar flux will 
be calibrated downward or will it stand?"

What Elwood refers to is when there is an unusually high solar flux 
reading, the NOAA Space Weather Forecast Center will report it as a 
lower value. I always assumed this was because the 10.7 cm receivers in 
Penticton were overloaded, but as Ken says, whether to change the value 
or not depends on what the data will be used for.

Ken responded: "I know that in the distant past there were attempts to 
'de-burst' flux values. However, it is not possible to do this with any 
accuracy at all. For example, at first sight it should be easy just to 
draw a line under the spike and use that value. However, in almost all 
cases the baseline is elevated by heating and some accelerated electrons 
beforehand and by heating and residual accelerated electrons afterwards. 
In some cases the baseline elevation lasts hours. In addition, with the 
on and off-source telescope motions that are an essential part of every 
measurement, it is even harder to separate what is going on.

"In addition, those who are using the fluxes for antenna calibration 
should have exactly what is measured. Some proxy applications need the 
whole flux too. So in the end the 'correction' process is application 
dependent, so our policy has been for some decades, tell the user what 
value we got, with no messing."

The reading Elwood referenced is the localnoonreading in Penticton on 
June 22, 2015. The three readings that day, at 1700 UTC, 2000 UTC and 
2300 UTC were 130.1, 246.9 and 127.2.

Checkingftp://ftp.swpc.noaa.gov/pub/indices/DSD.txtwe see that NOAA 
reduced that to 135.

The Australian Space Forecast Centre issued this warning at 0210 UTC 
June 26:

"The CME from region 2371 M7.9 flare is expected to arrive mid to late 
in the UT day on27Jun.

"INCREASED GEOMAGNETIC ACTIVITY EXPECTED DUE TO CORONAL MASS EJECTION 
FROM27-29 JUNE 2015.

"GEOMAGNETIC ACTIVITY FORECAST27 Jun: Minor Storm28 Jun: Active to Minor 
Storm29 Jun: Unsettled with Active periods."

ARRL Field Day is this weekend. I hope conditions remain calm!

If you would like to make a comment or have a tip for our readers, email 
the author at,k7ra at arrl.net <mailto: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 the
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 athttp://k9la.us/.

Archives of the NOAA/USAF daily 45 day forecast for solar flux and 
planetary A index are in downloadable spreadsheet format at 
http://bit.ly/1IBXtnGandhttp://bit.ly/1KQGbRm.

Click on "Download this file" to download the archive and ignore the 
security warning about file format. Pop-up blockers may suppress 
download. I've had better luck with Firefox than IE.

Monthly propagation charts between four USA regions and twelve overseas 
locations are athttp://arrl.org/propagation.

Instructions for starting or ending email distribution of ARRL bulletins 
are athttp://arrl.org/bulletins.

Sunspot numbers for June 18 through 24 were 82, 74, 89, 79, 77, 61, and 
39, with a mean of 71.6. 10.7 cm flux was 150.8, 137.3, 135.4, 131.7, 
135, 116.1, and 109.5, with a mean of 130.8. Estimated planetary A 
indices were 7, 5, 3, 8, 55, 76, and 17, with a mean of 24.4. Estimated 
mid-latitude A indices were 6, 4, 2, 7, 57, 47, and 15, with a mean of 19.7.
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