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ARRL Propagation Bulletin ARLP021 (2021)

SB PROP @ ARL $ARLP021
ARLP021 Propagation de K7RA

ZCZC AP21
QST de W1AW  
Propagation Forecast Bulletin 21  ARLP021
From Tad Cook, K7RA
Seattle, WA  May 21, 2021
To all radio amateurs 

SB PROP ARL ARLP021
ARLP021 Propagation de K7RA

Sunspot activity continues this week, although the average daily
sunspot numbers and solar flux have not really changed since last
week's report. This was not expected, because on the first day of
the reporting week in last week's Propagation Forecast Bulletin
ARLP020 there was no sunspot activity.

Average daily sunspot number hardly changed, from 21.1 to 20.3, and
average daily solar flux went from 74.3 to 74.2. I am surprised that
solar flux still remains below 80, since April 20.

Geomagnetic indicators were quiet, but values were slightly lower.

Average daily planetary A index changed from 9.1 to 6.6, and average
daily middle latitude A index went from 7.4 to 6.3.

Predicted solar flux for the next 30 days is 72 on May 21-27, 73 on
May 28, 75 on May 29-31, 77 on June 1, 78 on June 2-12, then 73, 77
and 77 on June 13-15, and 75 on June 16-27.

Predicted planetary A index is 10 and 8 on May 21-22, 5 on May 23
through June 10, then 8, 5, 10 and 8 on June 11-14, then 5, 10 and 8
on June 15-17, and 5 on June 18-30 and beyond.

Yesterday on Thursday planetary A index rose dramatically due to
increasing solar wind. The STEREO web site at
https://stereo.gsfc.nasa.gov/ has been a good indicator of
approaching sunspot activity about to rotate over the Sun's eastern
horizon, and currently on early Friday I can see a bright active
region about to become geo-effective.

OK1HH sends his geomagnetic activity forecast for the period May 21
to June 15, 2021.

"Geomagnetic field will be:
quiet on: May 25-26, (27-31,) June 9-10, 12-13
quiet to unsettled on: May 24, June 1-8
quiet to active on: May (21-23, June 11, 14)
unsettled to active: (June 15)
active to disturbed: none

"Solar wind will intensify on: May (21-25,) 28-30, June (7,) 9,
(14-15).

"Remarks:
- Parenthesis means lower probability of activity enhancement.
- Contradictory indications significantly reduce the accuracy of the
  forecast."

WB6VRN spotted a new location for the NOAA solar cycle progression
page, https://www.swpc.noaa.gov/products/solar-cycle-progression and
notes the site is interactive.

K1HTV reported, "On 17 meters during the late afternoon on May 18,
2021, I completed WAC (Worked All Continents), using the FT8 mode,
in 11 minutes. Around 3:15 AM EDT the next morning, after awaking
from a restless sleep and while still horizontally polarized, I
turned on my Android phone. I connected to my shack computer and its
3 video monitors using the VNC app.

"At that early hour (0715 UTC) here at my VA QTH, I found 17 Meters
was already open to Europe. I switched down to 30 Meter FT8 and
proceeded to work some DX. To my amazement, I was able to make FT8
contacts with all continents to complete WAC (Worked All Continents)
in 6 minutes even! Below is the K1HTV log for those contacts, which
may be a world record for WAC in the shortest time, at least for the
FT8 mode.

"30M FT8 WAC (Worked All Continents in 6:00 minutes

"OC - VK4PN - 2021-0519 07:25:00 started 1st QSO
EU - F2YT  - 2021-0519 07:26:30 send 73 to end 2nd QSO
AF - EA8AT - 2021-0519 07:27:45 sent 73 to end 3rd QSO
AS - JH1CCN - 2021-0519 07:28:30 sent 73 to end 4th QSO
NA - CO8LY - 2021-0519 07:29:30 sent 73 to end 5th QSO
SA - CE3ALY - 2021-0919 07:31:00 sent 73 to end 6th QSO and complete WAC

"All QSOs were made while running 75 Watts to the 30M trap dipole of
an A3WS antenna."

N4SO reports:

"I often listen to 28 MHz propagation beacons starting with VE3TEN
on 28.175 MHz, http://www.oarc.net/photos/ve3ten/ve3ten.html ending
at 28.300 MHz. I also have about ten 28 MHz beacons in the log from
0000-0100 UTC.

"From the HF Beacon Reflector and WJ5O for May 20 Evening 'GREYLINE'
my location.

"From 00:25-00:30Z, 20 May 2021 I can hear/identify ten 10-meter
beacon signals into EM71as.

"28.2025  KA3BWP     STAFFORD, VIRGINIA             1074 km 667 miles
28.208   WN2A/AK2F  BUDD LAKE , NEW JERSEY         1424 km 885 miles
28.216   K3FX       NEPTUNE CITY, NEW JERSEY       1424 km 885 miles
28.2313  N3TVV      JIM THORPE, PENNSYLVANIA       1364 km 848 miles
28.2327  N2MH       WEST ORANGE, NEW JERSEY        1449 km 869 miles
28.236   W8YT       MARTINSBURG, WEST VIRGINIA     1112 km 691 miles
28.246   KG2GL      NUTLEY, NEW JERSEY             1144 km 715 miles
28.269   AA1TT      CLAREMONT, NEW HAMPSHIRE       1763 km 1095 miles
28.2865  WB0BIN     SABIN, MINNESOTA               1900 km 1181 miles
28.296   W3APL      LAUREL, MARYLAND               1172 km 733 miles

"73 Bill WJ5O.

"Ken N4SO, EM50
Southern Alabama"

Jeff Hartley, N8II reported on Thursday:

"Hi Tad,

"The sporadic-E season has gotten off to a great start. Just in the
past 2 days, there were 3 sporadic-E 28 MHz openings into Europe! On
the 18th, I saw a spot for F4DSD in France on 10M SSB. We worked,
but just barely; after a struggle to copy my call, he gave me a 3x3
report at 2016 UTC. Hearing nothing else, I QSY'ed down to 15M CW
and worked GW3TMP in Wales and EA8TL in Canary Islands. Then I
managed to catch Hugh, EI2HI in Ireland and we exchanged 4x2
reports.

"The morning of the 19th featured a fairly widespread but weak
opening to EU on 10M.

"My first EU QSO was at 1410 UTC with ON7HJA in Belgium on SSB. Then
I heard Gyuri, HA5JI in Hungary who was the loudest of the opening,
S7 when we worked, then later near the end at 1433 UTC S5. Also
worked F8DGY and Germany on CW. I finally got back to the radio at
2015 UTC and quickly found DK7LX in Germany on 10M CW who was S7. As
we finished, Ron SP8ARY was calling me; we moved up and made a QSO;
he was my first 10M Polish QSO in my log started January 2017.

"Next I called a CW CQ once and was rewarded with a string of EU
callers from Germany, England, Czech Rep., Serbia, France, OZ4VW,
first Danish op in my 10M log (new band slot), Netherlands and 2
more Poles including SQ1921PS. many were rather weak.

"I then switched to SSB to find stronger signals as the opening
improved.  Ady, G6AD in England was S6 and Karel, ON2KP was S8.
3Z1921PS, Poland was a new SSB band slot as was 5P1B, Denmark 6
minutes later.  Of course, I found Ian, MM0TFU in Scotland about S7
who always seems to be there when 10M opens to NA. Calling CQ on
SSB, I worked a long string of EU stations with few if any CQs
needed to log the next station.

"The majority were in western EU, only one weak Italian. Additional
SSB countries logged were France, Netherlands, Northern Ireland,
Germany, and Austria. I made many QSOs with England. After 2128Z, I
searched out stations and found Nick, LZ3ND in Bulgaria who was
peaking over S9, no wonder with his 4 stacked 7 element Yagis! Also
worked LZ5DD. PI4DX also with stacked 6 element Yagis was S9.

"My last SSB QSO before dinner at 2158 UTC was S52WW, Slovenia for a
new band slot. Returning at 2238 UTC, I found Tom, 9A2AJ, Croatia on
CW (new slot), OA4DX, Peru on 12M CW for new slot, and Gordon,
MM0GPZ who was S7-8 on 10M SSB, S7 on 12M (my antenna only 2 el
Yagi), and a solid S9 on 15M. Despite the great conditions on 15M,
there was very little SSB or CW activity. My last 10M QSO was
EI7HBB, Ireland on SSB at 2318 UTC, a very long opening. I made in
total 64 10M QSOs with Europe.

"73, Jeff N8II"

Wow, Jeff!

Russ W4NI reports from Nashville:

"The solar storm on 12 May 2021 was not too bad. Despite K=7 at both
1200 and 1500 UTC, I was able to work DK, EA, LZ, 9A, on 20 CW from
Tennessee."

If you would like to make a comment or have a tip for our readers,
please email the author at, k7ra@arrl.net .

For more information concerning shortwave radio propagation, see
http://www.arrl.org/propagation and the ARRL Technical Information
Service web page 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/.

Instructions for starting or ending email distribution of ARRL
bulletins are at http://arrl.org/bulletins .

Sunspot numbers for May 13 through 19, 2021 were 24, 24, 24, 11, 11,
24 and 24, with a mean of 20.3. 10.7 cm flux was 74.7, 70.9, 73.3,
73.2, 74.8, 76.4, and 75.9, with a mean of 74.2. Estimated planetary
A indices were 7, 4, 8, 5, 6, 10, and 6, with a mean of 6.6. Middle
latitude A index was 7, 4, 8, 4, 6, 10, and 5, with a mean of 6.3.
NNNN
/EX