On Wednesday, December 19 Spaceweather.com displayed this headline:
"Solar minimum conditions are in effect," followed by
"The Sun has been without sunspots for 209 days in 2018--that is, 59% of
the time. To find a similar stretch of blank Suns, you have to go back
to 2009 when the Sun was experiencing the deepest solar minimum in a
century."
Looking at my own records, I show the average daily
sunspot number for all of 2009 was 5.05, and average daily solar flux
was 70.6.
Looking at the past two months (October 19 through
December 19) the same values were 3.6 and 69.4, so we are clearly down
in the same sort of minima.
Of course, there are many ways to slice and dice
the numbers, so rather than 3.6 and 69.4 from the past two months,
looking at all the numbers for 2018 so far, we see averages of 6.6 and
69.9. Average daily sunspot numbers for the past week were 3.4 (there
were only two days with any visible sunspots) which was down from 9.7 in
the previous week.
Average daily solar flux declined only slightly from 70.7 to 70.4.
Average planetary A index decreased from 8 to 4.1, while average mid-latitude A index went from 6.4 to 3.
Predicted solar flux for the next 45 days is 70 on
December 21-23, 72 on December 24, 70 on December 25-27, 72 on December
28 through January 4, 70 on January 5-16, 72 on January 17-31, and 70 on
February 1-3.
Predicted planetary A index is 8, 5 and 5 on
December 21-23, then 8, 5 and 5 again on December 24-26, then 8 on
December 27-28, then 12, 10 and 8 on December 29-31, 5 on January 1-2,
then 10, 12, 10, 10 and 8 on January 3-7, 5 on January 8-12, 8 on
January 13, 5 on January 14-23, then 8, 12, 10 and 8 on January 24-27, 5
on January 28-29, then 10, 12, 10, 10 and 8 on January 30 through
February 3.
Geomagnetic activity forecast for the period December 21 to January 16, 2019 from F.K. Janda, OK1HH.
"Geomagnetic field will be:
Quiet on December 23, 25-27, January 10-12 Quiet to
unsettled on December 21-22, 24, January 9, 13 Quiet to active on
December 28, January 1-2 Unsettled to active on December 29, (31),
January (3-5,) 6-8, 14 Active to disturbed on December (30,) January
(15-16)
"Solar wind will intensify on November 30 and on December (24-27,) 28-31, January 1, (3-4,) 5-7, (8, 14,) 15-16
"Remark: - Parenthesis means lower probability of activity enhancement."
Here is an exchange between W8BYA and N0JK about their activity during the Geminid meteor shower, which peaked on December 14:
"Hi Jon, so excited just had to share with you. After
over 6-7 years of trying KE7NR/P in DM54ah and myself completed on 2m MS
using MSK144 several days before the Geminid peak date. I had a good
feeling when right off the bat I received this +20 dB decode from him:
"150700 20 20.2 1527 & W8BYA KE7NR DM54
"Anyway, this was very late AM and represents my best 2m non-EME DX at 1425 miles and non-EME grid #373.
"Gedas, W8BYA
"I ended up with 9 Geminids m/s Qs on 6 meters. All
MSK144. Best DX probably W3CP EM74. Some fairly short distance M/S Qs
such as KV5W EM22 and K0TPP EM48. Saw decodes on K0WDO EM17, N0LWF EN10,
and several on KA9CFD EN40 - which are fairly close in and would imply
high MUF. I was on early morning Dec. 14.
"100 w, 3 el Yagi.
"Jon N0JK"
The latest from Dr. Tamitha Skov, the Space Weather Woman:
https://youtu.be/wt-T-mbt5Ag
If you would like to make a comment or have a tip for our readers, email the author at k7ra@arrl.net.
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Sunspot numbers for December 13 through 19, 2018
were 0, 12, 12, 0, 0, 0, and 0, with a mean of 3.4. 10.7 cm flux was
70.2, 70.8, 71.2, 69.8, 70.1, 70.4, and 70.2, with a mean of 70.4.
Estimated planetary A indices were 3, 3, 2, 2, 6, 7, and 6, with a mean
of 4.1. Estimated mid-latitude A indices were 2, 3, 1, 1, 5, 5, and 4,
with a mean of 3.
• All propagation reports can be found at:
http://www.southgatearc.org/propagation
