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ARRL Propagation Bulletin ARLP049 (2020)

ARLP049 Propagation de K7RA

QST de W1AW  
Propagation Forecast Bulletin 49  ARLP049
From Tad Cook, K7RA
Seattle, WA  December 4, 2020
To all radio amateurs 

ARLP049 Propagation de K7RA

Sunspot cycle 25 is a year old, and increasing solar activity
continues to surprise and amaze.

Average daily sunspot numbers more than doubled every week over the
past few weeks. ARLP047 reported average daily sunspot numbers of
12, then last week the average was 27.9, and now this week we report
the average daily sunspot number at 57.6.

In the past week the highest daily sunspot number was 84 on Sunday,
November 29, and solar flux also peaked that day, at 116.3, pushing
the week's average solar flux to 108.1, up from 90.1 over the
previous seven days and 79.8 in the week prior to that.

Geomagnetic indicators were moderate, despite several solar flares
reported on Jon Jones, N0JK reports that on
November 29 at 1311 UTC earth orbiting satellites detected the
biggest solar flare in over 3 years. But it was not earth directed,
so magnetometers on earth indicated nothing unusual.

But this is a sure sign that activity is increasing.

Predicted solar flux over the next 45 days is 100, 95, 90, 85 and 80
on December 4 to 8, 75 on December 9 to 11, 85 on December 12, 82 on
December 13 to 16, 85, 90 and 100 on December 17 to 19, 105 on
December 20 and 21, 108 on December 22, 110 on December 23 to 25,
115 on December 26 and 27, 113 on December 28 to 30, 110 on December
31, 105 and 103 on January 1 and 2, 2021, 95 on January 3 and 4, 92
and 88 on January 5 and 6, 85 on January 7 and 8, 82 on January 9 to
12, then 85, 90, and 100 on January 13 to 15 and 105 on January 16
and 17.

Planetary A index is predicted at 5 on December 4 to 17, then 12, 20
and 8 on December 18 to 20, 5 on December 21 and 22, 8, 10 and 8 on
December 23 to 25, 5 on December 26 2020 through January 13, 2021,
then 12, 20, 8 and 5 on January 14 to 17.

Geomagnetic activity forecast for the period December 4 to 29, 2020
from F. K. Janda, OK1HH.
"Geomagnetic field will be
Quiet on: December 6 and 7, 12 and 13, (14 to 16) 
Quiet to unsettled on: December 8 to 11, 21, 28 
Quiet to active on: December 4 (and 5), 17, 22 and 23, 26, 29
Unsettled to active: December 18, 20, (24) and 25, (27)
Active to disturbed: December 19
Solar wind will intensify on December 4, (5 to 8, 11, 19,) 20 to 22,
(23,) 27 (28 and 29)
Parenthesis means lower probability of activity enhancement."

Jeff Hartley, N8II reports from FM19cj in Shepherdstown, West

"About 10 days does not make an average, but I can never remember
such a sudden sustained increase in SFI as the new cycle begins.
Perhaps October 1978 may have been similar, but assume flux was
already fairly high in the preceding months and the new cycle was
only about a year from the peak.

Conditions or at least activity seemed to be down a bit in the week
preceding the CQWW CW contest until Friday which seemed better. 20M
was a bit disappointing at the Saturday November 0000Z start with
most DX coming from Southern South America.

D4Z on Cape Verde was loud and continued to be through most of the
weekend on 20.

I managed a marginal scatter with Italy beaming at 150 degrees (over

Moving to 40 at 0023Z signals were loud from Germany and Hungary
farther south. At 0121Z 7Q6M Malawi and CR3W Madeira Is. were logged
easily on 40. On 80M at 0220Z I could work EU excluding Russia north
of the Black Sea area and the Baltic states, but signals were not
that loud. 160M was very tough with large pile ups on NA DX and not
much readable from Africa or Europe.

I resumed on 20M at 1158Z about 10 minutes before sunrise and the
band was already full of loud Europeans even open already to Russia.
Signal levels were very good with high activity. R8WF in Asia but
still in the EU Russian zone 16 was my best DX to the east.

By 1309Z signals from EU were building nicely on 15M from nearly all
corners. Some of my first contacts were OH3077F in Finland, RL6M
southern Russia, LY4T Lithuania, and UT7NY Ukraine. By 1430Z,
Northern EU was mostly gone on 15M, but I maintained a good EU QSO
rate until about 1522Z. A brief visit to 10M then found Spain (very
weak), Canary Is., Puerto Rico, French Guiana, and Cayman Is. Then
it was back to 20 with good western EU conditions until about 1700Z
staying there working EU until 1721Z. 5H3EE Tanzania went into my
15M log at 1735Z.

Starting at 1741Z 10M was open well to Chile, Argentina, and a bit
less well to Brazil. The 10M SA opening was starting to fade at
1900Z. Back on 20M at 1927Z there was a good auroral sporadic E
opening to Scandinavia on 20M. ZM1M New Zealand had a good long path
signal at 1953Z as did VK4TS Queensland, Australia shortly after.

On 15M starting at 2015Z, I worked New Zealand, Australia, Hawaii,
and Alaska. A quick check of 10M at 2105Z yielded 5 contacts with
loud Hawaiians! The first Japanese station, JA1ZGO I worked at
2125Z, but the auroral curtain was like a wall and only big gun JA's
were worked through 2355Z. I heard 3 Chinese stations due north from
here, but no contacts were made.

At sunset 2151Z, southern SA was loud and I was thrilled to work
JR1GSE Japan at 2157Z. The low band conditions were not good to
northern EU on any band during the evening, but 40 did stay open to
some extent to southern EU through 0200Z. 80M EU signals were down,
and on 160 very weak.

I managed some quick QSOs on 40 to UN9L Kazakhstan, VK3GI Australia,
and ZM1A New Zealand starting at 1133Z. 20M was not fully open to EU
at 1152Z, but much better 10 minutes later.

I logged many EU over the next 70 minutes and was thrilled to be
called by EX8MJ Kyrgyzstan who was weak, and UN0L. At 1304Z, I found
good EU signals on 15M and soon there were some incredibly loud
signals 20 to 30db over S9! Even stations in N and NE EU were very
workable but weaker.

4L6QL, Georgia was my best DX to the east. At 1424Z, there was a
weak opening to EU on 10M logging Italy, Slovak Rep., and France,
and CR3DX on Madeira, AF. Later at 1524Z on 10, I found ZD7BG, St.
Helena Is., and at 1603Z Croatia, Germany, Italy, Portugal, and 7Q6M
Malawi. CR6K in Portugal was still heard at 1730Z, very late! The
opening to EU on 15M lasted late, still okay but fading at 1650Z. I
was able to keep a good EU QSO rate going on 20 through 1743Z, much
later than Saturday."
On December 3, N7RP reported from New Mexico:

"This morning a little after 8 AM local time, I worked HS0ZGC
(Thailand) on 12 meters on FT8. He was working South American
Stations and I did not see any other US stations work him other than
myself. I am just running 100 W to a vertical, so I have no idea
what path it was. It was amazing, since it must have been around
midnight there. He immediately uploaded to LOTW, so the contact is

Look up N7RP on to read his great narrative about his life
in ham radio. Not to be missed!

6,000 km TEP contact between Aruba and Argentina on 2 meter SSB

Mike Schaffer, KA3JAW reported from Easton, Pennsylvania FN20jq. 

"On Monday, November 30, 11 meter CB (27 MHz) was very active from

Even if you're under heavy rain, with severe thunderstorms you still
can detect stations via sporadic-e (Es) well past the 2,600 mile
(4184 km) range.

The radio background noise levels varied between 3 to 5 dBm on the 
signal strength meter.

Below are places that I heard, distance, and sporadic-e hops.
AZ (Tempe) - 2072 miles (3334 km) (2x) 
CA (Los Angeles) - 2384 (3836 km) miles (2x) 
CA (San Diego) - 2366 miles (3807 km) (2x) 
CO (Denver) - 1567 miles (2521 km) (1x) 
MT (Bozeman) - 1823 miles (2933 km) (2x) 
NM (Albuquerque) - 1749 (2814 km) (1x) 
NV (Los Vegas) - 2167 miles (3487 km) (2x) 
OK (Oklahoma city) - 1261 miles (2029 km) (1x) 
PR (San Juan) - 2625 miles (4224 km) (2x) 
TX (San Antonio) - 1524 miles  (2452 km) (1x) 
TX (El Paso) - 1839 miles (2959 km) (2x) 
UT (Salt Lake City) - 1908 miles (3070 km) (2x) 
WA (Seattle) - 2349 miles (3780 km) (2x) 
Canada, Alberta (Calgary) - 1974 miles (3176 km) (2x) 
Canada, British Columbia (Vancouver) - 2377 miles (3825 km) (2x) 
Jamaica (Kingston) - 1569 miles  (2525 km) (1x)" 

Newspaper coverage of solar flare:

And NYC image:

Frank Donovan, W3LPL shared this several days ago:

"A solar flare from massive solar region 2786 at 1311Z on Sunday 29
November was the most powerful solar flare and coronal mass ejection
(CME) thus far during solar cycle 25. The sun's activity is now
rapidly increasing after a slow increase in activity this year
following solar minimum last December. 

The flare and CME erupted from just behind the southeast solar limb
and was not Earth directed. The shock enhancement/glancing blow from
the CME may cause unsettled to active geomagnetic conditions on 1
and 2 December. There is a chance for additional M-class solar
flares through 2 December and a slight chance for much stronger
X-class flares. 

The WSA-Enlil model shows the 29 November solar flare and associated
CME. Earth is the yellow dot."

For more information concerning radio propagation, see and 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

Instructions for starting or ending email distribution of ARRL
bulletins are at .

Sunspot numbers for November 26 through December 2, 2020 were 43,
60, 67, 84, 62, 46, and 41, with a mean of 57.6. 10.7 cm flux was
105.8, 106.3, 109.6, 116.3, 109.4, 104.1, and 104.9, with a mean of
108.1. Estimated planetary A indices were 7, 8, 10, 6, 8, 2, and 4,
with a mean of 6.4. Middle latitude A index was 5, 7, 9, 6, 6, 2,
and 4, with a mean of 5.6.


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