SB PROP @ ARL $ARLP040
ARLP040 Propagation de K7RA
ZCZC AP40
QST de W1AW
Propagation Forecast Bulletin 40 ARLP040
> From Tad Cook, K7RA
Seattle, WA September 30, 2016
To all radio amateurs
SB PROP ARL ARLP040
ARLP040 Propagation de K7RA
Australia's Space Weather Services issued a geomagnetic warning at 0022 UTC on
September 29:
"The geomagnetic conditions are expected to vary between active levels to major
storms for the next three days. This is because the solar winds are expected to
be in excess of 600 km/s associated with a very large positive polarity coronal
hole. The storm intensities are expected to be slightly stronger than that
observed in the previous two solar rotations (previous rotation Ap was 32)
associated with this coronal hole because the earth-sun coupling efficiency is
highest during the equinox periods. Thus there is chance that aurora may be
visible on the local nights of 29 September from Tasmania and some parts of
Victoria, Australia.
"INCREASED GEOMAGNETIC ACTIVITY EXPECTED DUE TO CORONAL HOLE HIGH SPEED WIND
STREAM FROM 29 SEPTEMBER 2016 TO 01 OCTOBER 2016
"GEOMAGNETIC ACTIVITY FORECAST
29 Sep: Minor Storm
30 Sep: Minor Storm
01 Oct: Active to Minor Storm"
This week's (September 22-28) average daily sunspot numbers and solar flux
changed little from the previous seven days. Average daily sunspot numbers
changed from 29.9 to 29.7, and average daily solar flux declined just two
points from 83.4 to 81.4. Average planetary A index was much higher, changing
from 8.9 to 19.7, and average mid-latitude A index changed from 7.6 to 12.3.
Projected solar flux for the near term is 81 and 78 on September 30 through
October 1, 80 on October 2-3, 82 and 85 on October 4-5, 90 on October 6-14, 95
on October 15-18, 90 on October 19-21, 85 on October 22-27, 80 on October
28-31, 85 on November 1-3, and 90 on November 4-10.
Predicted planetary A index is 38, 30, 20, 14, 12, 10 and 6 on September 30
through October 6, 5 on October 7-14, then 8, 10, 20, 10, on October 15-18, 5
on October 19-22, then 18 and 12 on October 23-24, 35 on October 25-27, then
25, 20, 16, 10 and 8 on October 28 through November 1, 5 on November 2-10, and
8 on November 11.
Here is the weekly geomagnetic forecast from F.K. Janda, OK1HH of the Czech
Propagation Interest Group:
"Geomagnetic activity forecast for the period September 30-October 26, 2016
"Geomagnetic field will be:
Quiet on October 9-10, 13,
Mostly quiet on October 7, 11, 14, 20,
Quiet to unsettled on October 5-6, 8, 15-16, 19, 21,
Quiet to active on October 1-3, 5, 12, 17-18, 23-24
Active to disturbed on September 30, October 4, 22, 25-26
"Increases of solar wind from coronal holes are expected on September 30,
October 1-3 and 15-17."
On September 24 Jim McLelland WA6QBU of Santa Rosa, California sent this:
"Just a quick note about DX. I noted last night that conditions were quiet on
20 meters, which is unusual for me on the West Coast, with sunspots at 30, SFU
at 85 and a quiet Sun. Therefore, moving to 40 meters, I found the band open to
South Africa and worked Bill, ZS6CCY who was 10 dB over S9. Keep up the good
work."
Then on September 30 he wrote, "Mr. Cook, One more thing - 10 meters was open
to Hawaii (SSB) from the West Coast last weekend and again Tuesday early
evening."
Mark Ammann, KM0A had some comments about VHF propagation enhanced by aurora in
a September 28 email:
"I always enjoy reading your propagation updates via ARRL email member list,
and especially the personalized experiences you include. Having been on 2
meters and 6 meters for almost 40 years, aurora is always fascinating yet rare,
more so on 2m since it provides DX distances normally unattainable on that
band, save for extended tropo or the rare E-skip opening. I wanted to add to
your
comments re Jon N0JK's aurora during the 2m sprint.
"2 meter aurora CW signals, in my opinion, are not 'buzzy' or 'distorted,' but
actually very easy to copy unless the signals are extremely weak. They sound
more like a hollow whisper. Sound clips
are below of actual aurora signals.
"As for aurora on 6 meter SSB, signals are distorted somewhat but easy to copy
if one speaks slowly. As for 2m SSB, signals are much distorted and very
difficult to comprehend. Sounds almost like the person is gargling rocks!
"Keep up the good work!"
Mark included links with audio samples of CW and SSB signals received via
auroral propagation.
http://www.n4st.com/aurora_cw.wav
http://www.dxmaps.com/sounds/2mssba.mp3
Ted Leaf, K6HI of Kona, Hawaii sent this about using NVIS antennas on 40
meters:
"If of interest, you may want to put this out. We have nets, all year across
the Hawaiian Island chain at 4pm/0200 UTC on 40M, with our low antennas
barefoot, it is NVIS out to 200 miles. Sometimes very noisy, but usually work
all stations."
NVIS is Near Vertical Incidence Skywave propagation. Here are some references:
http://www.w0ipl.net/ECom/NVIS/nvis.htm
http://www.qsl.net/wb5ude/nvis/
http://hflink.com/propagation/
Jon Jones, N0JK of Lawrence, Kansas sent this report early Friday morning,
September 30:
"With the Fall Equinox and geomagnetic storms this week due to a fast moving
stream of solar wind, 10 meters has come alive on north - south paths. The last
couple of days Uli, VP6AH has had a loud signal on 10 meters to North America.
He is running just 100 watts and a dipole antenna and was over S-9 on my mobile
Sept. 27 about 2015z. H44GC, VK9NZ, FY5KE, VP8LP and others have also been
active on 10."
And finally, a story about a geomagnetic disturbance in 1941. Thanks to WW1ME
who forwarded this from the Southgate Amateur Radio News:
https://eos.org/features/the-geomagnetic-blitz-of-september-1941
If you would like to make a comment or have a tip for our readers, email the
author at k7ra@arrl.net.
For more information concerning radio propagation, see the ARRL Technical
Information Service 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 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 September 22 through 28 were 30, 49, 47, 18, 23, 21, and
20, with a mean of 29.7. 10.7 cm flux was 85.1, 85.5, 84.9, 84.6, 86.8, 85.6,
and 84.4, with a mean of 81.4. Estimated planetary A indices were 4, 4, 5, 23,
22, 38, and 42, with a mean of 19.7. Estimated mid-latitude A indices were 4,
3, 4, 12, 18, 21, and 24, with a mean of 12.3.
NNNN
/EX
)\/(ark
Always Mount a Scratch Monkey
Do you manage your own servers? If you are not running an IDS/IPS yer doin' it
wrong...
... The advantage of exercising every day is that you die healthier.
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* Origin: (1:3634/12.73)
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