ARRL

ARRL Propagation Bulletin ARLP009 (2012)

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 2, 2012
To all radio amateurs 

SB PROP ARL ARLP009
ARLP009 Propagation de K7RA

Average daily sunspot number this week was down 12 points from the
previous week. Solar flux was about the same.

With February over, we can look at some of our averages and
statistics for the current sunspot cycle. The average daily sunspot
number for February 2012 was 50.1, the lowest monthly value since
January 2011.  The monthly averages for sunspot numbers since
January 2011 are 32.2, 53.5, 81.1, 80.8, 61.5, 55.5, 67.2, 66,
106.4, 123.6, 133.1, 106.4, 91.4 and 50.1.

We also keep track of a three-month moving average, and the latest,
ending in February and centered on January, 2012 is 83.3. This is
the numeric average of all the daily sunspot numbers from December
1, 2011 through February 29, 2012, a period of 91 days. 83.3,
centered on January, is the lowest since August 2011, when the
average was 79.6.  The 3 month moving averages of daily sunspot
numbers centered on August 2011 through January 2012 are 79.6, 98.6,
118.8, 118.6, 110 and 83.3.

The latest prediction has planetary A index for March 2-6 at 8, 8,
5, 10 and 10, then 5 on March 7-10, 8 on March 11, 5 again on March
12-16, then 12, 15, 10, 8 and 5 on March 17-21.

Predicted solar flux is 105 on March 2-5, 100 on March 6-8, 105 on
March 9-11, 110 on March 12-13, and 115 on March 14-18. 110 is the
predicted value on March 19-20 and 105 on March 21-25, and that
covers the spring equinox.

The ARRL International SSB DX Contest this weekend should have
fairly good conditions. It looks like somewhat unsettled conditions
for Friday and Saturday, March 2-3, and quiet geomagnetic conditions
on Sunday, March 4.

A new service that forecasts geomagnetic storms for satellite
operators is at http://www.fp7-spacecast.eu/. You can find more
details at,
http://www.eurekalert.org/pub_releases/2012-03/bas-nst030112.php.

From time to time we mention silly popular press reports of large
solar flares and other big space weather, but this article from
Northern Scotland places the famous Carrington event at the peak of
Sunspot Cycle 19, instead of the nineteenth century:
http://www.johnogroat-journal.co.uk/Features/Solar-superstorm-could-be-on-the-way-7642279.htm.


Robert Miles, K9IL of Martin, Tennessee wrote about 6 meters: "This
is the low time for most USA 6 meter operators, unless you are very
far south. I have been listening for the Oceania stations that
others are spotting, and on Wednesday February 23 (0200z Thursday) I
worked Remi, FK8CP (New Caledonia) on 6 meter CW, a pretty good
thrill for me in EM56, NW Tennessee."

That is quite a long haul, about 7,900 miles from Robert's place on
Green Acres Drive to Noumea.

Mel Frost, KD7DCR at 6,200 feet near Whitehall, Montana writes about
6 meter plans for this year: "Just thought I'd mention that more and
more, plans to activate some rare grids here in the USA area this
season (May-August) are becoming known. Some of these are personal
travel plans and some are dedicated trips with only radio in mind.

"There is one big-circle route from Arizona to North Dakota, around
eastern North Dakota for about a month, and then back around the
Western side to Arizona. This one is kind of early in the year, but
may work well if our Sun cooperates, eh? Some Canadians are planning
to activate the other CY0, St Paul Island.

"The far northern Michigan grids (mostly water) are going to get a
go, and the biggy is a special trip down into DL88, and DL79/89 is
laid on with some large antennas and power. And not much said
currently, but there is also a 'floating' operation for DM02 planned
as well (very rare!). These are all concentrated on 6 meters, with
some higher bands being available if open."

Lance Collister, W7GJ of Frenchtown, Montana writes about
moonbounce: "I noticed your comments in the last propagation
bulletin about the low band guys enjoying the low solar activity.
Actually, at the other end of the spectrum, the unusually low Kp
index also makes for ideal 6 meters EME conditions!  And with the
greatly increasing number of newer transceivers (and amplifiers)
that include 6 meters, and with more stations QRV on digital modes,
many folks have 6 meter EME capability and don't even realize it! I
have been activating a rare DXCC on 6 meter EME for each of the last
4 years, and will be going to ZK2 (Niue) at the beginning of
September (during the optimum time of the month for 6 meter EME).
Any halfway decent 6 meter station with good ground gain should be
able to put that rare DXCC in the log during their moonset. The
smallest antenna I have worked so far with my portable 6 meter EME
setup was N3CXV and his M2 6M5X Yagi during his moonset.

"More information about 6m EME and using JT65A mode for EME is on my
web page http://www.bigskyspaces.com/w7gj/.

"It is REAL MAGIC on the Magic Band when you can make contacts
halfway around the world during a poor solar cycle!"

Howard Lester, N7SO of Schuylerville, New York wrote, "I haven't
been on HF for nearly 2 months, but got on this morning (February
24) at 1600z. Even with the flux at 'only' 103, I had a nice, but
short chat on 10 meter SSB with 9A9DX, Ljubo (in Croatia), with
S7-S8 signals both ways. Then, on 12 meter CW I heard an F6 station
with a booming signal from France. If this is what 10 and 12 can be
like at this time of year with this level of solar flux, I have no
complaints."

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 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. Find more good
information and tutorials on propagation at
http://myplace.frontier.com/~k9la/.

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 29 were 52, 47, 47, 58, 45,
35, and 22, with a mean of 43.7. 10.7 cm flux was 103.3, 108.9, 108,
107, 105.5, 103.3, and 102, with a mean of 105.4. Estimated
planetary A indices were 4, 6, 6, 6, 16, 10, and 6, with a mean of
7.7. Estimated mid-latitude A indices were 3, 6, 3, 7, 12, 11, and
6, with a mean of 6.9.
NNNN
/EX