SB PROP @ ARL $ARLP013
ARLP013 Propagation de K7RA
ZCZC AP13
QST de W1AW
Propagation Forecast Bulletin 13 ARLP013
> From Tad Cook, K7RA
Seattle, WA March 31, 2017
To all radio amateurs
SB PROP ARL ARLP013
ARLP013 Propagation de K7RA
Solar activity rose over the past week, with average daily sunspot numbers
rising from 3.4 to 29.7 and solar flux from 71.2 to 77.9.
Average daily planetary A index increased from 10 to 18.3, and average
mid-latitude A index went from 7.1 to 13.6.
Predicted solar flux is 86, 87 and 88 on March 31 til April 2, then 86, 84, 83
and 82 on April 3 to 6, 71 on April 7 to 14, 73 on April 15 to 17, 75 on April
18 to 22, 78 on April 23 to 26, 75 on April 27 to 29, 73 on April 30 to May 1
and 71 on May 2 to 11.
Predicted planetary A index is 20 on March 31 through April 2, 15 on April 3
and 4, 12 on April 5 and 6, 5 on April 7 to 16, then 24, 25 and 10 on April 17
to 19, 5 on April 20 to 22, then 25, 40, 35, 20, 18 and 12 on April 23 to 28,
and 8, 16, 12, 15 and 12 on April 29 through May 3, followed by 5 on May 4 to
13 and 24 on May 14.
F.K. Janda, OK1HH sent us his geomagnetic activity forecast for the period
March 31 to April 25, 2017.
"Geomagnetic field will be:
quiet on April 9 and 10, 14 to 16, 20 to 22
mostly quiet on April 6, 8, 11
quiet to unsettled April 4, 12 and 13, 19
quiet to active on April 3, 5, 7, 23, 25
active to disturbed on March 31, April 1 and 2, 17 and 18, 24
Amplifications of the solar wind from coronal holes are expected on March 31,
April 1 to 4, (5 to 8,) 12 and 13, (14,) 16 to 20, 25.
Remark:
- Parenthesis means lower probability of activity enhancement and/or lower
reliability of prediction."
Tamitha Skov released a space weather video last week:
http://bit.ly/2obVYcb
Jon Jones, N0JK reported: "Aurora contacts reported on 6 meters March 27 along
the northern tier states and Canada. This was due to a G2 geomagnetic storm
from coronal wind stream."
Scott Bidstrup, TI3/W7RI sent this from Costa Rica:
"Don't know if you've seen this, but a magnetic precursor event to solar flares
has been discovered, that may actually lead to short-term warnings before a
flare occurs.
https://phys.org/news/2017-03-igniting-solar-flare-corona-lower-atmosphere.html
The six meter drought that everyone has been complaining about up there has
been even worse for us down here in the single-digit latitudes. It's been at
least six months since I've logged a six meter QSO. In the wake of coronal
hole passages, there have been a couple of evenings recently with some very
modest TEP openings from here into Brazil and Argentina, but with only a small
handful of stations heard weakly and no new stations not already worked many
times. There has been no sporadic E at all for many months - not even hearing
the beacons from Venezuela and French Guiana that indicate our most common
openings to the east. If there is supposed to be an inverse correlation
between solar activity and sporadic E, like the textbooks claim, you could have
sure fooled me.
Not that there has been no sporadic E at all; indeed, there has been very
frequent Sporadic E openings into South America on 10m in the daytime here, and
even frequent evening TEP openings into South America on 10m as well. But the
signals are about what we would normally expect on six meter openings rather
than ten. MUFs from these events just aren't getting very far into the VHF.
Conventional F2 openings on ten have become very rare now.
Other propagation on the upper HF bands has been poor - the declining solar
activity has taken a big toll here on the upper HF bands, with most band
openings starting later in the morning than in
the past, and ending earlier in the late afternoon - and signals not being
particularly strong when the band is open. The only saving grace has been that
our mid-day break has been shorter and weaker than at the solar maximum, so
it's often possible to hear signals and even work them at midday on 20m, which
has not been possible at higher sunspot numbers. MUF has gotten high enough to
open 17m on most days, but often it doesn't quite make it to 15m. So when 15m
is open, it's often the result of a weak sporadic E event or the aftermath of a
coronal hole passage. During the last solar minimum, 15m would be open most
days, but so far during this one, it's been hit and miss at best. And the
solar minimum is just getting a good start.
30m has been the most reliable performer - almost always open into the States
during the day and worldwide at night. Sadly, PSK activity seems to have
declined on 30m, so I haven't worked as many
stations with the ragchews I dearly love, just the spartan JT9 contacts. Sure
wish we had phone privileges on that band.
40m has been seeing a huge increase in QSO activity with conditions on 20m
declining. There are evenings now where finding an open spot can be a bit of a
problem. Most of what I hear on phone here is the States, but I am seeing a
lot of eastern European DX on PSK, and my good friend, Michael, TI7XP, has
worked some pretty good DX on 40m CW in recent days, including Kuwait and
several stations in the Far East, and a lot of VK/ZL. The DX here is
definitely improving on 40m.
60m is still not available here, and all of us here are holding our breath,
waiting for a response from the FCC on the League's petition for rulemaking,
allowing 100w. activity up there on the new WARC 60m band. If it happens for
the States, it would be terrific news for us - another piece of terrific
ammunition in our fight to get access to 60m here. There are still no Central
American countries that allow access to 60m yet. And I can't see a good reason
why not - there is almost no local commercial or government activity in that
portion of the spectrum here.
80m is seeing an improvement, especially in DX as the solar activity declines.
My good friend in Panama, Jay, HP3AK, is working Japan on most morning
greylines, and often getting quite good reports. VK/ZL is being worked more
frequently, too - often several times per week. And nighttime Old World DX is
more frequently heard now than it was just a year ago. Several of my local
friends report working Europe with fairly modest 80m installations. Signal
levels from the States' 75m evening ragchews have been noticeably stronger than
in the past, too. Nighttime D-layer hasn't responded as much to the rising
cosmic ray flux as I would have expected by now.
Noise levels on 160m have been low enough this winter that some of the locals
are getting more interested in top band. TI7XP has a new skywire loop up for
that band, and has worked some good DX on it. But the summer noise season is
just about here, and I don't expect the interest will last long.
And finally, I am pleased to report that I have copied four experimental
beacons on 630m from the States, and have sent the corresponding WSPR decodes
to the operators, who were delighted for the reports from here. Most nights,
when noise levels aren't particularly high, I can hear at least one or two,
with just a G5RV at 50 feet and an ordinary IC7200 tuned to the appropriate
frequency. Enough success to demonstrate that QSOs with Central America from
the States should be possible with modest stations on that band. Not much hope
for 630m access here though, at least until it has become a major band in the
States like it now is in Europe, so we can justify access to it here. I have
checked the 2190 band, but so far, I haven't copied anything yet."
For more information concerning radio propagation, see the ARRL Technical
Information Service 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 March 23 through 29, 2017 were 12, 12, 11, 20, 49, 51, and
53, with a mean of 29.7. 10.7 cm flux was 72, 72.3, 74, 77.2, 82.8, 83.7, and
83.3, with a mean of 77.9. Estimated planetary A indices were 11, 6, 4, 4, 54,
28, and 21, with a mean of 18.3. Estimated mid-latitude A indices were 9, 7,
3, 3, 34, 22, and 17, with a mean of 13.6.
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...
... Any beer is better than no beer. Olympia is no beer.
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* Origin: (1:3634/12.73)
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