SB PROP @ ARL $ARLP045
ARLP045 Propagation de K7RA

ZCZC AP45
QST de W1AW  
Propagation Forecast Bulletin 45  ARLP045
From Tad Cook, K7RA
Seattle, WA  November 14, 2022
To all radio amateurs 

SB PROP ARL ARLP045
ARLP045 Propagation de K7RA

ARRL headquarters was closed on Friday, November 11, so this
bulletin is delayed until Monday, but edited and updated Sunday
night.

Two new sunspots appeared November 1, one more November 3, two more
November 4, one more and then another on November 6 and 7, another
on November 9 and again on November 10, and one more on November 13.
But sunspot numbers and solar flux seem modest lately, and so are
the solar flux forecasts.

Average daily sunspot numbers rose this week, from 70.3 to 78.9, yet
somehow the solar flux averages stayed the same, 129.9 and 129.9.
Our reporting week is Thursday through Wednesday, and in the four
days since, the average rose to 137.9.

Average daily planetary A index went from 13.7 to 13.4, but the
middle latitude numbers changed from 14.3 to 9.6.

Predicted solar flux is 135 on November 14-15, 120 and 110 on
November 16-17, 105 on November 18-19,  then 110, 114, 112 and 114
on November 20-23, 116 on November 24-26, 118 on November 27-28,
then 120, 122, 125, 124 and 122 on November 29 through December 3,
130 on December 4-5, then 125 and 120 on December 6-7, 115 on
December 8-9, then 120, 118, 116, 115 and 114 on December 10-14, 116
on December 15-16, 114 on December 17-18, then 112 and 114 on
December 19-20, and 116 on December 21-23.

Predicted planetary A index is 5 on November 14, 10 on November
15-16, 5 on November 17-19, 15 on November 20,  5 on November 21-22,
then 8, 16, 26, 15 and 12 on November 23-27, then 8, 15, 26, 16 and
12 on November 28 through December 2, then 8 on December 3-4, 12 on
December 5-8, 8 on December 9, then 5 on December 10-14, then 25, 15
and 8 on December 15-17, 5 on December 18-19, then 8, 26 and 15 on
December 20-22.

Angel Santana, WP3GW, wrote:

"10 meters is getting so better, that today on November 9 at 1319
UTC had a contact with 3B9FR on 28.522 MHz up 5. He even answered me
in Spanish."

That is Rodrigues Island, in the Indian Ocean, more than 9000 miles
from Puerto Rico.

More on Rodrigues Island:

https://bbc.in/3El5MGS

A new video from Dr. Tamitha Skov, WX6SWW:

https://youtu.be/tkpwp_oUMnQ

Solar flares and radio blackouts:

https://bit.ly/3EkBFzu

https://bit.ly/3hkvke8

Paul, K2PMD, asked:

"I am a relatively new ham, so please forgive me if this is a dumb
question. Generally speaking, I understand that a high K index makes
radio communication more difficult. Why is the K index not included
in the weekly propagation report?"

My response:

"The reason is, there are too many of them.  Instead, geomagnetic
indicators are summarized using the A index.

"If we listed all the K indices for both middle-latitude and
planetary, there would be 112 numbers to report.

"K index is quasi-logarithmic, while A index is linear.

"The A index for any day is calculated from the 8 daily K indices.

"https://bit.ly/3zLPLXW

"I've been using this resource more and more lately, when I want to
check for possible geomagnetic disturbances in real time:

"https://www.swpc.noaa.gov/products/planetary-k-index

"Notice that the numbers are fractional, and it is easy to spot
trends in real time. K index is always expressed in whole numbers,
but because these are planetary numbers from many magnetometers, you
get a finer resolution."

Send your tips, reports, observations, questions, and comments to
k7ra@arrl.net.

For more information concerning shortwave radio propagation, see
http://www.arrl.org/propagation and the ARRL Technical Information
Service 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 November 3 through 9, 2022 were 65, 81, 82, 78,
80, 85, and 81, with a mean of 78.8. 10.7 cm flux was 125.3, 117.7,
131.1, 130.8, 134.6, 132.3, and 137.6, with a mean of 129.9.
Estimated planetary A indices were 26, 16, 10, 4, 19, 12, and 7,
with a mean of 13.4. Middle latitude A index was 16, 12, 8, 3, 12,
8, and 8, with a mean of 9.6.
NNNN
/EX