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ARRL Propagation Bulletin ARLP027 (2012)

ARLP027 Propagation de K7RA

QST de W1AW  
Propagation Forecast Bulletin 27  ARLP027
From Tad Cook, K7RA
Seattle, WA  July 6, 2012
To all radio amateurs 

ARLP027 Propagation de K7RA

Solar activity jumped way up this week, with average daily sunspot
numbers increasing by nearly 92 points to 118.1.  Average daily
solar flux went to 138.5 from 92.8 the week before.  One new sunspot
group appeared on June 29, another on July 1, and two more on July
Geomagnetic activity this week was concentrated on June 30 through
July 2, and the causes were the usual suspects, solar flares and
solar wind spewing from coronal holes.  One unusual aspect was that
the mid-latitude A index, measured in Virginia, was actually higher
on July 3-4 than the planetary A index, which is usually higher.
The planetary A index is made up of an weighted aggregate of
estimated K index data from multiple geomagnetic observatories.
The outlook for the near term has changed since the forecast that
was presented on Thursday in the ARRL Letter.  The solar flux is
higher, and the higher geomagnetic activity is because of an M-Class
solar flare on July 4.
The forecast shows increasing activity over the next couple of days,
with solar flux at 165 on July 6-7, 160 and 155 on July 8-9, 145 on
July 10, 140 on July 11-12, then 130, 125, 115 and 110 on July
13-16, and 105 and 100 on July 17-18.  Solar flux is expected to dip
below 100 on July 19-22.  Solar flux is expected to rise to 140 on
July 30 through August 1, dip again, and then peak at 145 on August
Planetary A index is expected at 8, 12, 22, 18, 8 and 7 on July
6-11, and 5 on July 12-26, followed by another active period with
planetary A index at 20 on July 27-28, 15 on July 29-30, and 8 on
July 31 through August 1.  A index should go quiet down to 5 over
the next couple of weeks, except for a reading of 8 on August 4.
Petr Kolman, OK1MGW of the Czech Propagation Interest Group predicts
the geomagnetic field will be quiet to unsettled July 6-7, quiet to
active on July 8, unsettled to active July 9, mostly quiet on July
10-12, unsettled to active July 13-15, mostly quiet on July 16-18,
and quiet to unsettled on July 19-21.
The Australian Space Forecast Centre issued a Geomagnetic
Disturbance Warning at 2328 UTC on July 5.  They predicted quiet to
unsettled conditions July 6, quiet to unsettled conditions with
active to minor storm periods late in the UTC day on July 7, and
unsettled to active conditions with isolated minor storm periods on
July 8.
This alert comes from a mail list offered by the Australian
Government Bureau of Meteorology.  You can see the email lists
offered at and example on
subscribing at  This is for
the Geophysical Warning email list, but notice that on the listinfo
page at the first URL that the text string to the left of the
Geophysical Warning description is ips-geo-warning, which matches
the end of the second URL above.  Just substitute the appropriate
string of characters in that URL for any other lists you want to
subscribe to.
As June is now over, we can look at some monthly numbers and 3-month
moving averages.  For the 3-month periods centered on January
through May 2012, the average daily sunspot numbers were 83.3, 73.7,
71.2, 87.3 and 91.5.  Keep in mind that the 3-month average centered
on May is an arithmetic average of all daily sunspot numbers from
April 1 through June 30.
If we look at just the monthly sunspot number averages for September
2011 through June 2012, they are 106.4, 123.6, 133.1, 106.4, 91.4,
50.1, 78, 84.5, 99.4 and 90.1.
That period last fall when sunspot numbers were so high was unusual,
or at least we hadn't seen activity such as that in a long time.  It
was eight years earlier, in November 2003 when the monthly average
of daily sunspot numbers was over 100 previous to September 2011.
In November 2003 the average daily sunspot number was 103, and in
October 2003 it was 118.9.  It hadn't passed the November 2011
average of 133.1 since 9 years ago when it was 132.8 in July, 2003.
On July 20, 2003 the daily sunspot number was 224.
Go to and in the Archives drop-downs toward
the upper-right, set it for July 21, 2003.  Then click the Back and
Forward links toward the upper right and see all the sunspot
activity as it moves across the sun.  If there seems to be a one-off
problem with the sunspot numbers in the archive, it
displays the previous day's sunspot number because the date has
changed to the next UTC day by the time the daily sunspot number is
updated.  You can check it against the daily sunspot numbers in our
bulletin at
to see what I mean. ran an article on a recent solar flare.  Read it at
Also, NASA commented yesterday:
Following last week's reports, another Field Day report came in on
July 3 from Billy Bagwell, KE5WLH of the Greyhound Amateur Radio
Club at Eastern New Mexico University in Portales, New Mexico.
Billy wrote, "K5R, the special event station celebrating 100 years
of New Mexico statehood had three radios on 80, 40, 20, and 15
meters.  We made plenty of contacts on all bands.  80 got better
here after 9:00 PM local time and was great most of the night with
times of noise and fading.  We think this was due to sun
event/magnetic activity.  20 and 40 were hot as we expected.  15
meters started slow at noon and moved with the Sun from East to West
until sunset when it seemed to fade away.  On Sunday at sunrise 15
meters came back hard and moved with the Sun as expected.  We had
our stations set up in the Roosevelt County Sheriffs Office EOC, and
all involved had a great time!"
On June 30, Bob Leo, W7LR of Bozeman, Montana wrote about a "giant 6
meter opening yesterday morning, the best that I have ever heard in
75 years of hamming.  The band was full of distant DX.  I even
worked Israel, Poland, Estonia and Svalbard with 100 watts, all new
ones for me between 1300z to 1500z when the band folded.  Today it
is as dead as a fence post."
Bob was born in 1921 and was on the famous Hallicrafters expedition
to Africa in 1948.  Check out his bio at,
which of course requires a free account and login.
Joe, CT1HZE of Portugal (IM57nh) reports "June 30 was definitely an
historic day for 6 meter multi-hop Es.  Already from 0430z observers
in Finland received FM broadcast stations from Russia on 70 MHz
indicating a MUF greater than 110 MHz at high latitudes of up to 70
degrees N."
"These Es clouds shifted westerly with the sun and at about 1300z a
spectacular 6 meter opening started when the automatic keyer from
NN7J (CN85, Beavercreek, Oregon) was heard simultaneously by G0JHC,
CT1HZE and stations in Germany.  In the following 6 hours Pacific
Northwest stations from W6, W7, VE7, VE6 and VE5 were able to work
hundreds of QSOs with many countries in Western, Central, and
Eastern Europe."
"Highlights were QSOs between JW7QIA and W7 (OR) and W5 (TX)
stations and W7MEM and Israel (10700km).  Even W7GJ who stated for
years that he would never work EU on terrestrial modes was able to
work 9 QSOs with EU into G, SP, F and DL.  CT1HZE was able to work
25 stations from the Pacific Northwest, after waiting for more then
a decade for such an opening.  Best DX was VE7DAY CO70 and WB8VLC
CN84 who used 35W and a 5 el. only.  Several QSOs were even made on
"Due to the early local time on the West coast probably many
stations missed the first hours of the opening and later on some had
to go to work, of course.  I would consider this as a multihop Es
propagation event with high MUF (over 70 MHz) on huge parts of the
paths and probably more hops than necessary for the distance, i.e. 5
or 6 hops for the 8000 to 9000 km paths considering observed
elevated angles with which the signals were received."
Thanks, Joe, and Bob.  What an opening!
Kevin Lahaie, K7ZS of Hillsboro, Oregon wrote on June 29, "Out of
the blue Europe opens this morning on 6 meters in a big way!  I just
worked DL, F, GM, SM, SP, ON, IT9 and OZ on 6 meter CW.  Yahoo!"
Apparently the opening may have favored the northwest and not the
southwest.  I hope he wasn't so discouraged that he missed the
opening, but early on June 29, Lance Wilson, NR7N of Scottsdale,
Arizona wrote: "I have been on 6 meters for fifty years and I must
say that the E-season in the Southwest has been disappointing.  We
have had a few good openings this year to the East Coast but nothing
like previous years.  International DX is non-existent.  I keep
watching reports on extensive East Coast to Europe
openings (as well as extensive U.S. openings for them as well) while
we on the other side of the country go empty handed."
"While working Europe from the west normally requires F2 it appears
that something else may be at play here.  Day after day of seeing
the left-hand lower quarter of the U.S. virtually blank makes me
wonder what could be going on.  Openings, when they occur, are
mainly to the northwest with some also to the middle of the country.
Even our normal pipeline to Texas appears to be down."
Regarding conversion of Command sets to SSB, a topic mentioned in
recent bulletins, Ray Soifer, W2RS of Green Valley, Arizona wrote:
"The W2EWL conversion didn't exactly convert a Command set to SSB,
it made it into a VFO to use with an SSB exciter.  In the 1950s I
had a Central Electronics 20A exciter and a converted BC-458 VFO.
The 20A generated SSB (upper sideband) at 9 MHz.  Mixing that with
the 5 MHz output of the BC-458 produced USB on 20 meters or LSB on
If you would like to make a comment or have a tip for our readers,
email the author at,
For more information concerning radio propagation, see the ARRL
Technical Information Service at  For an explanation of
the numbers used in this bulletin, see  An archive of
past propagation bulletins is at  Find more good
information and tutorials on propagation at
Monthly propagation charts between four USA regions and twelve
overseas locations are at
Instructions for starting or ending email distribution of ARRL
bulletins are at
Sunspot numbers for June 28 through July 4 were 73, 97, 90, 137,
165, 136, and 129, with a mean of 118.1. 10.7 cm flux was 119.7,
117.4, 124, 133.4, 165.9, 145.8 and 163.2, with a mean of 138.5.
Estimated planetary A indices were 6, 5, 22, 19, 19, 10, and 9, with
a mean of 12.9.  Estimated mid-latitude A indices were 7, 6, 21, 20,
18, 11, and 11, with a mean of 13.4.


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