- Amateur Radio (Ham Radio) Community

Call Search

New to Ham Radio?
My Profile

Friends Remembered
Survey Question

DX Cluster Spots

Ham Exams
Ham Links
List Archives
News Articles
Product Reviews
QSL Managers

Site Info
eHam Help (FAQ)
Support the site
The eHam Team
Advertising Info
Vision Statement

[Articles Home]  [Add Article]  

Propagation Forecast Bulletin #03 de K7RA:

from W1AW Bulletin via the ARRL on January 19, 2018
Add a comment about this article!

Propagation Forecast Bulletin #03 de K7RA:

Propagation Forecast Bulletin 3 ARLP003
>From Tad Cook, K7RA
Seattle, WA January 19, 2018
To all radio amateurs

ARLP003 Propagation de K7RA

It was a quiet week in space weather (January 11-17) with 0 sunspots over the weekend and geomagnetic indicators rising only slightly.

Compared to last week, average daily sunspot numbers declined from 11.9 to 7, but average daily solar flux went from 69.9 to 70.7. Seems counter-intuitive that sunspot and solar flux would move in opposite directions, but these are all very low numbers anyway, and any change is slight. Also, there are no sunspot numbers between 0 and 10 due to the arcane and somewhat confusing way they are counted. The number gets 10 points for each sunspot group, and one point for each sunspot in those groups. Therefore the minimum possible sunspot number if there is any sunspot activity is 11.

Geomagnetic indicators were quiet, with average daily planetary A index moving from 5.4 to 6.1, and mid-latitude A index from 4.6 to 4.9.

Predicted solar flux is 71 on January 19-25, 72 on January 26-27, 70 on January 28 to February 17, 72 on February 18-23, and 70 on February 24 to March 4.

Predicted planetary A index is 8, 15, 12, 12, 10 and 8 on January 19-24, 5 on January 25-27, 10 on January 28, 5 on January 29 to February 3, 8 on February 4-5, 5 on February 6-8, then 8, 12 and 10 on February 9-11, 5 on February 12-14, 20 on February 15-16, 18 and 12 on February 17-18, 5 on February 19-23, 10 on February 24, 5 on February 25 to March 2, and 8 on March 3-4.

Geomagnetic activity forecast for the period January 19 to February 14, 2018 from F.K. Janda, OK1HH and the Czech Propagation Interest Group.

"Geomagnetic field will be:
Quiet on January 19, 30-31, February 3, 6-8
Mostly quiet on February 2, 9
Quiet to unsettled on January 23-27, 29, February 1
Quiet to active on January 20-21, 28
Active to disturbed on January 22, February (4-5, 10)

"Amplifications of the solar wind from coronal holes are expected on January 20-23, 28-31, February 5-6, (7, 9,) 10-12

- Parenthesis means lower probability of activity enhancement.
- Current forecasts are continuing to be less reliable."

Interesting article about preserving a long running hand-drawn record of solar images:

For the latest from Dr. Tamitha Skov see:

If you would like to make a comment or have a tip for our readers, email the author at

For more information concerning radio propagation, see the ARRL Technical Information Service web page 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

Sunspot numbers for January 11-17, 2018 were 12, 0, 0, 0, 12, 13, and 12, with a mean of 7. 10.7 cm flux was 70.8, 70.9, 70.8, 70.5, 70.2, 71.1, and 70.9, with a mean of 70.7. Estimated planetary A indices were 2, 4, 7, 14, 9, 4, and 3, with a mean of 6.1. Estimated mid-latitude A indices were 2, 3, 7, 11, 7, 3, and 1, with a mean of 4.9.

Source: W1AW Bulletin via the ARRL.

There are no comments on this article: Post One

Email Subscription
My Subscriptions
Subscriptions Help

Other News Articles
Syracuse to Students Talk to Astronaut on International Space Station:
NASA's SDO Reveals How Magnetic Cage On the Sun Stopped Solar Eruption:
FCC Considering Licensing Frequencies Above 95 GHz:
IARU Region 3 Disaster Communications Committee Chair Jim Linton, VK3PC SK:
Propagation Forecast Bulletin #08 de K7RA: