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ARRL Propagation Bulletin ARLP030 (2018)

ARLP030 Propagation de K7RA

QST de W1AW  
Propagation Forecast Bulletin 30  ARLP030
From Tad Cook, K7RA
Seattle, WA  July 27, 2018
To all radio amateurs 

ARLP030 Propagation de K7RA

A single small sunspot appeared on July 21, then disappeared.
Previous to that, no sunspots appeared since June 26.  The daily
sunspot number on July 21 was 11, which is the minimum non-zero
sunspot number.

Because there were no sunspots over the previous week, average daily
sunspot numbers increased from 0 to 1.6, while average daily solar
flux for the week declined from 71.8 to 68.4.

Average daily planetary A index changed from 6.4 to 8.1, and average
daily mid-latitude A index (measured in Virginia) increased from 6.1
to 8.

Predicted solar flux is much lower than recently expected.  Expected
flux values (based on the July 26 prediction) are 66 on July 27
through August 2, 67 on August 3, 68 on August 4 to 10, 70 on August
11 to 18, 68 on August 19 through September 6, and 70 on September 7
to 9.

Predicted planetary A index is 5 on July 27 to 31, 18 and 8 August 1
and 2, 5 on August 3 to 11, 8 on August 12 and 13, 5 on August 14
and 15, then 7, 12, 5, 10, 25 and 15 on August 16 to 21, then 10 on
August 22 and 23, 8 on August 24 and 25, 5 on August 26 through
September 7, and 8 on September 8 and 9.

F.K.  Janda, OK1HH sends us this geomagnetic activity forecast for
the period July 27 to August 22, 2018.

"Geomagnetic field will be:
Quiet on July 28 to 30, August 5, 11, 15
Quiet to unsettled on July 27, 31, August 10, 14, 16
Quiet to active on August 1, 6 to 9, 12, 19
Unsettled to active on August 3 and 4, 17, 20, 22
Active to disturbed on August 2, (13, 18,) 21

Solar wind will intensify on July (30 and 31) and August (16 to 19,)
20 to 22

- Parenthesis means lower probability of activity enhancement.
- Configuration of active areas in the Sun is changed, which
temporarily reduces the reliability of predictions."

The latest from D. Skov, including her latest video:

Dear Tad,

Surprisingly, our Sun continues to stay busy-- perhaps it missed the
solar minimum memo?  The latest blast of fast solar wind hitting
Earth this week has already caused us to reach active conditions and
we have a few more days under its influence before things calm back
down.  Although not at storm level, aurora over the past few days
has been reported as far south as Germany in Europe and as far south
as Michigan in the USA.  Special thanks to Cornelius B and Martin D
for these insider field reports!

Even though we are getting auroral propagation with this storm on
Earth's night side, sustained communication via amateur radio
continues to suffer on Earth's dayside.  We will have to wait nearly
another week for a new bright region to rotate into view and boost
the solar flux.  We might see radio propagation improve slightly at
the beginning of next week.  At least GPS/GNSS users should continue
to enjoy decent reception on Earth's dayside.

Finally, I want to personally say THANKS for all the wonderful
feedback I have gotten on my Patreon rewards tiers.  I have been
slammed preparing for a trip to Belgium this week and I still have
some emails to write in response to your insightful suggestions and
encouraging comments.  So if you haven't yet received a response
from me, it is coming!  By the way, next week I will be doing my
forecast remotely.  This means I have to leave my production camera
behind and go "low-tech." It's always an adventure!

Cheers, Tamitha

Jeff N8II in West Virginia wrote on July 24:

"It has been a thrilling and bit exhausting last 3 days with 10
meter multi-hop sporadic E openings to Europe late Saturday morning
the 21st, and both morning and late afternoon/evening Sunday and
Monday!  I can never remember such good consistent EU openings on Es
any year and the odds are even more against it being a month after
the summer solstice.  I got to the radio late Saturday morning past
1500Z and suspect the band had been open to EU for a while already.
Over less than 2 hours, I worked 23 EU QSO's and 2 with Africa.  The
majority were with Mediterranean area countries, Spain, France, and
Italy also working 3 Germans, England, and the Czech Republic.
Besides those QSO's, I heard over 10 Spanish stations working each
other in a contest on CW.  I worked the following new DXCC band
slots, IS0 Sardinia, S01WS Western Sahara, and probably 7V5D Algeria
(weak).  In the evening, I made 6 double hop QSO's with CA and
several single hop into TX and MO.

Sunday, I was on earlier probably about the time the band was
opening.  There were at least 2 Spanish stations still working their
contest, EA4URE gave me a signal report.  I made 7 EU QSO's most
with Germany; most signals were fairly weak.  I also found on CW
LZ2HR in Bulgaria with a S7 signal for a new band slot.  Also worked
was PJ2Y, Curacao probably via Es.  By 2112Z, the band was open
again working Italy, Spain, Switzerland, Hungary (HA9RT loud), and
new band slots Z68M Kosovo, and 9A2EU Croatia.  I now have worked
Kosovo our newest DXCC country on all bands 80 through 10 meters CW
and 4 bands SSB this year.  Also worked on 15M phone were Lauro
IK4GRO (loud), Italy, Spain, and Tonno ES5TV in Estonia (quite a

Today, Monday I made it to the radio at 1350Z and obviously there
was a good EU to EU and later EU to Middle East opening already
taking place.  After a CW QSO with England and a hello to Ian,
MM0TFU (s7) who always seems to be there when there is Transatlantic
Es, I started CQ'ing and had a run of 16 mostly very good copy
stations from Northern Ireland, England, Wales, Scotland, Austria,
Italy, France, and Germany.  Then it was off to mostly search for DX
on CW working HB0/PC5A Liechtenstein, and HA9RT Hungary (loud as
usual).  But by far the most amazing event was hearing HZ1TT in
Saudi Arabia running EU stations about 1/3 of which I could hear!  No
QSO (have worked 7Z1SJ in past year), but amazing to hear his S1 to
4 solid copy signal for over 10 minutes.  This was a first for me to
hear Es into the Arabian Peninsula on 10M.  At 1946Z, I returned to
work Tony T77C, San Marino (new band slot).  Mostly on SSB, I worked
France, Italy (some over S9), Germany, Portugal, Austria, and Spain
mostly answering my CQ's.  Around 21Z on CW, I found E79D Bosnia and
CT3MD Madeira Islands (S9) for new band slots."

When asked about six meters, on July 24 he wrote:

"Oh yes quite a few EU to TX and Midwest as well as east coast
QSO's.  When I heard HZ1TT, there was a 9K2 working EU on 6M.  Most
all 6M DX is worked via FT8 on 50313 KHz which allows decoding about
18 to 20 db BELOW the noise level.  I just feel the technology has
made it too easy, but that is the way of the DX world.  There is
halfway decent 10M SSB and CW activity.  I have not worked EU since
Monday on 10, was away today, but the reports of Es were very
minimal Wed."

For more information concerning radio propagation, see the ARRL
Technical Information Service at  For an explanation of
numbers used in this bulletin, see

An archive of past propagation bulletins is at  More good
information and tutorials on propagation are 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 July 19 through 25, 2018 were 0, 0, 11, 0, 0, 0,
and 0, with a mean of 1.6.  10.7 cm flux was 70.5, 70.5, 70, 68.2,
67, 66.9, and 65.8, with a mean of 68.4.  Estimated planetary A
indices were 4, 7, 11, 5, 4, 17, and 9, with a mean of 8.1.
Estimated mid-latitude A indices were 4, 7, 10, 5, 4, 16, and 10,
with a mean of 8.


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