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The K7RA Solar Update

11/20/2020

Tad Cook, K7RA, Seattle, reports: As solar flux declined over the past week, I noticed less long-distance propagation on 10 meters reported on pskreporter.info from my local grid square, CN87. Propagation on 12 meters was quite strong, however. After 0100 UTC on November 15, transequatorial propagation was evident between East Asia and Australia on 10 meters. 

Solar activity declined dramatically over the past week, with average daily sunspot numbers going from 31.3 to 12. On November 15 and 16, there were no sunspots at all, which greatly affected the decline in this week’s average. Solar flux weakened from a weekly average last week of 90, to 79.8 this week. 

Predicted solar flux over the next 45 days is also relatively weak, at 75 on November 20 – 21; 73 on November 22; 70 on November 23 – 26; 72 on November 27; 75 on November 28 – December 8; 72 on December 9 – 10; 70 on December 11 – 12; 75, 72, and 72 on December 13 – 15; 70 on December 16 – 22; 72 on December 23 – 24, and 75 on December 25 – January 3, 2021.

Predicted planetary A index is 8, 12, and 8 on November 20 – 22; 5 on November 23 – December 2; 8 on December 3 – 4; 5 on December 5 – 17; 8, 12, 8, 10, and 12 on December 18 – 22; 5 on December 23 – 29; 8 on December 30 – 31, and 5 on January 1 – 3, 2021.

Here’s the geomagnetic activity forecast for November 20 – December 16, from F.K. Janda, OK1HH. The geomagnetic field will be: 

  • quiet on December 1, 6 – 8, 12 – 14, (15 – 16) 
  • quiet to unsettled on November 28 – 30, December 2, 4, 10 – 11 
  • quiet to active on November 26 – 27, December 3, 5, 9 
  • unsettled to active November (20,) 21 – 22, (23 – 25) 
  • active to disturbed  –  None predicted 
  • Solar wind will intensify on November (20,) 21 – 25, (30,) December (2,) 3 – 5, (9).

Notes:

  • Parentheses mean lower probability of activity enhancement. 
  • Predictability of changes remains lower, because there are few unambiguous indications.

This bulletin has mentioned the paper by McIntosh, et al, “Overlapping Magnetic Activity Cycles and the Sunspot Number: Predicting Sunspot Cycle 25 Amplitude,” referenced in The ARRL Letter for November 19.

My favorite passage: “Our method predicts that SC25 could be among the strongest sunspot cycles ever observed, and that it will almost certainly be stronger than present SC24 (sunspot number of 116) and most likely stronger than the previous SC23 (sunspot number of 180). This is in stark contrast to the consensus of the SC25 [prediction panel] sunspot number maximum between 95 and 130, i.e., similar to that of SC24.” The Solar Cycle 25 Prediction Panel met in September.

The new prediction is very exciting, and suggests a cycle that may rival Cycle 19, which peaked in March, 1958. The effects on HF radio propagation at that time were remarkable and included daily worldwide propagation on 10 and even 6 meters, and not just during daylight hours.

I was about to turn 6 years old at the time, and we lived in Reedley, a small fruit-packing town in California’s San Joaquin Valley, where my father worked supplying agricultural chemicals to farmers. He drove a company car that contained a low-band VHF FM radio (probably 30 – 40 MHz, judging from my memory of the bumper mounted antenna), and I recall his describing being unable to contact the base station in Fresno, about 25 miles away, while getting interference from other users of the channel in Texas.

I’ve heard from many hams who were new Novice licensees at the time and assumed conditions would always be as they were then. They have been waiting a long time. I would love to see daily sunspot numbers greater than 200. Here’s an article about sunspot activity in 1958.

NN4X reported from Florida on 12-meter FT8 activity on November 14.

“12 meters was in great shape!

134500

 

1

 

0.1

 

1225

 

~

 

DL1EZ

 

TZ1CE

 

–14

 

134500

 

3

 

–0.5

 

1596

 

~

 

OQ4U

 

KM8AM

 

R–07

 

134500

 

20

 

0.5

 

1786

 

~

 

PY2GG

 

EA8TH

 

R+12

 

134500

 

13

 

0.3

 

2058

 

~

 

SM7DLK

 

WA8NLX

 

EM92

 

134500

 

9

 

0.2

 

1976

 

~

 

CQ

 

OZ7PBI

 

JO45

 

134500

 

2

 

–0.4

 

1712

 

~

 

SV2DFK

 

V51LZ

 

RR73

 

134500

 

0

 

0.0

 

2107

 

~

 

CQ

 

EA1DR

 

IN82

 

134500

 

–9

 

0.1

 

629

 

~

 

9J2BS

 

EA4CYQ

 

IM78

 

134500

 

–20

 

–0.2

 

1393

 

~

 

9J2BS

 

YB9WIC

 

R–13

 

134500

 

–18

 

0.0

 

994

 

~

 

CQ

 

S79VU

 

LI75

 

134530

 

20

 

0.5

 

1786

 

~

 

PY2GG

 

EA8TH

 

R+12

 

134530

 

28

 

0.1

 

862

 

~

 

EA8AAH

 

W4AFB

 

EL98

 

134530

 

–5

 

–0.4

 

1712

 

~

 

4Z4DX

 

V51LZ

 

R+01

 

134530

 

–13

 

0.1

 

1225

 

~

 

DL1EZ

 

TZ1CE

 

–14

 

Mike Schaffer, KA3JAW (FN20jq), wrote:

“Yikes, October out-of-season single-hop sporadic-E is active on the 6 meter band along the east coast! On Saturday, October 17, 2100 – 2300 UTC, it is 25 days past the autumnal equinox. Once again, the unexpected happens during the early recovery out of a solar minimum. I was monitoring FT8 on 50.313 MHz for Es to show up along the Gulf of Mexico coastal region. Then it happened — the first direct decodes in monitoring mode: W4KBX in EL98 (central Florida) and K2IL in EL97 (south-central Florida, north of Lake Okeechobee.

“Now that the band is open with Es expanding farther south, I decided to try for any contacts down on the SSB calling frequency, 50.125 MHz. When I rolled down there, several operators were already having conversations about how pleasant [it was] that the band came back to life since the summer months.

“At 2252 UTC, I put out the first CQ, and AG4N, Bill from West Point, Georgia, very close to the Alabama state line replied. From my QTH to AG4N, azimuth 230°, distance 771 miles. I gave Bill a 4 × 7 signal report with QSB. 

“The Es was being funneled as far away as Mobile, Alabama (996 miles), and Biloxi, Mississippi (1,045 miles).

“By 2335 UTC, the band started to collapse with signal reports sliding down to 2 × 2. No double-hop Es from Puerto Rico, Dominican Republic, or other northern Caribbean Sea islands was heard.

“Even if the band conditions sound dead, I urge everyone to continue monitoring the 6-meter SSB calling frequency, 50.125 MHz, then take it one step farther and call CQ. You might be pleasantly rewarded, even if you are running 10 W into a 6-meter horizontal half-wave dipole less than 8 feet off the ground.”

Here is the November 14 forecast from the Space Weather Woman, WX6SWW.

Sunspot numbers for November 12 – 18 were 27, 24, 11, 0, 0, 11, and 11, with a mean of 12. The 10.7-centimeter flux was 85.1, 81.9, 80.2, 78.7, 76.6, 79.1, and 77.3, with a mean of 79.8. Estimated planetary A indices were 3, 3, 3, 4, 2, 3, and 4, with a mean of 3.1. Middle latitude A index was 3, 2, 2, 2, 0, 3, and 3, with a mean of 2.1.

For more information concerning radio propagation, visit the ARRL Technical Information Service, read “What the Numbers Mean…,” and check out K9LA’s Propagation Page.

A propagation bulletin archive is available. For customizable propagation charts, visit the VOACAP Online for Ham Radio website.

Instructions for starting or ending email distribution of ARRL bulletins are on the ARRL website. 

Share your reports and observations. 



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