[CQ-Contest] Update - Contest Propagation (CQ WW SSB)

[Tomas (NW7US)]

>http://www.foxnews.com/story/0,2933,100981,00.html

I don't think that this news story fully explores the current event. The latest 
warning/alert forecast for this is as follows:

(From NOAA):
Forecast for next 24 hours:

Space weather for the next 24 hours is expected to be minor.
Geomagnetic storms reaching the G1 level are expected.
Radio blackouts reaching the R1 level are expected.

This takes into account that the IMF is mostly oriented toward the north. When 
this is oriented south (Bz is negative), then it will affect the geomagnetic 
field. But, if north (Bz is positive), then it will not affect the geomagnetic 
field.

When the CME glances the Earth's magnetosphere, the IMF has to be south (Bz 
negative), if it were to cause a geomagnetic storm. The thinking at this time is 
that the Bz will not go negative, or if it will, it will not go very far. Thus, 
the geomagnetic activity level should not go too high, at most minor storm level 
during the late afternoon and early evening of the 24th (local time).

By the way, the large sunspot is not the cause of geomagnetic storms. The IMF 
and solar wind speed, along with enhancements from CMEs, cause geomagnetic 
storminess. If the sunspot group throws a flare, however, we might have a short 
radio blackout.

The forecast is for minor to moderate flaring.

So, what is in store for the contest (CQ WW SSB) weekend, starting tomorrow?

Solar activity is drastically higher than just a week ago. Now, we have two very 
large sunspot groups. Things look great, in terms of the flux levels expected.

On the other hand, what is in store for the geomagnetic activity and flare 
activity? The latest forecast created on 21 October, 2003 shows the following:

2003 Oct 24   165     20     4
2003 Oct 25   165     15     3
2003 Oct 26   165     10     3
2003 Oct 27   165     10     3

Now, from NOAA/SEC, we have this issued on 22 October, 2003:

The geomagnetic field is expected to be at predominantly active levels through 
day one of the forecast period. The partial halo CME from today is expected to 
arrive mid-day on the 24th of October and may produce periods of major storming. 
Day three should see a return to unsettled to active conditions.

Predictions for flare activity are:

Event Probabilities 23 Oct-25 Oct

Class M  70/70/70
Class X  30/30/30
Proton   15/15/20
PCAF    yellow

Expected flux:

Penticton 10.7 cm Flux
Observed  22 Oct     154
Predicted  23 Oct-25 Oct 160/165/170

And, Ap numbers/Geomagnetic conditions:

Geomagnetic A Indices
Observed Afr/Ap 21 Oct 028/039
Estimated Afr/Ap 22 Oct 020/038
Predicted Afr/Ap 23 Oct-25 Oct 020/030-040/045-015/025

Geomagnetic Activity Probabilities 23 Oct-25 Oct
A. Middle Latitudes
Active        40/30/30
Minor storm      25/40/20
Major-severe storm  10/25/05
B. High Latitudes
Active        45/25/40
Minor storm      35/40/25
Major-severe storm  15/30/10

Looking at all of the data, I think that at most we will have active geomagnetic 
activity for most of the contest. Combined with the very high flux, however, the 
conditions for most bands at and below 15 meters should be hopping!

Specifically, I predict that the start of the contest (at 0000Z on 24 October, 
2003, which is evening time for most of the USA) will be somewhat rough - polar 
paths and paths over high latitudes will be degraded more than mid-latitude 
paths. Higher bands will shut down quickly. Low bands should be fair. The full 
day of Saturday will fare better. Perhaps, because of the lower Ap and expected 
Kp, along with stronger Flux, we'll see great conditions as high as 15 meters. 
10 might still show promise. While the geomagnetic field will be active for the 
remainder of the period, it will be decreasing. That can make lower bands hot.

So - I would try my luck at it. Think of it - a flux of 150 to possibly as high 
as 200. That will open up the higher bands and will also open up many paths 
around the world throughout the day and possibly during the night, on 40 through 
20. Geomagnetic activity will degrade the strength and duration of the openings 
on the highest bands, but not as closed as it could have been if the flux was at 
or slightly below 100, as it has been lately. Again, I think that the combined 
high flux and the moderately active geomagnetic field will balance out for good 
to possibly excellent conditions depending on the band and time of day, and so 
forth.

Of course, it is possible that the sun will surprise us, with massive flares and 
that the Bz will turn sharply and strongly south.  If that were to happen, spend 
time with family and friends.  :)

73 de Tomas, NW7US (AAR0JA/AAM0EWA)
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