[HCDX] MAJOR FLARE/GEO STORM : NW7US Propagation Bulletin Update 0930 UTC 17-I-2005

[nw7us@xxxxxxxxxxx]

NW7US Propagation Bulletin Update
0930 UTC, 17 January 2005

It is clear now after analysis that the coronal mass ejection (CME)  
associated with the X2.6-class X-ray flare of 2302 UTC 15 January 2005 has  
arrived.  The first detection was at 0640 UTC as an energetic ion  
enhancement.  The second was a moderate shock reported at 0716 UTC by ACE.

This is the second CME expected between 16 and 18 January 2005.  The first  
CME, associated with the long-duration M8.6-class flare of 15 January 2005  
(0639 UTC), appears to have arrived around 0930 UTC 16 January 2005, when  
we saw the planetary K index (Kp) reach 5, and the solar wind speed  
increase with a change in the interplanetary magnetic field (IMF).

The second CME that has now arrived is pushing the solar wind speed to  
above 600 kilometers per second.  The IMF has been become  
southward-oriented for only short periods of time.  However, I expect the  
IMF to move more steadily southward as this CME plasma cloud passes,  
increasing the geomagnetic disturbance already detected.  As stated  
earlier, forecasters are expecting major to severe geomagnetic storminess  
in the next 12 hours, extending for the next 24 to 48 hours.  This will  
depress the maximum usable frequencies on HF ionospheric radio paths.  At  
the same time, these conditions are and will continue to spawn Aurora.   
Radio Aurora has been reported.

As I write this (0930 UTC), it is also clear that we are in the middle of  
another long-duration X-class flare.  The rise-time of this flare event  
has been over one-hour in length, and the peak has not yet been reached.  
This is an event to keep our eyes on, as any CME associated with this will  
likely cause at least a glancing blow in about three days.  During the  
course of this flare, radio blackout is causing degradation of HF  
communications on the day-lit side of the Earth.  The flare was declared  
as an active event at 0659 UTC (17 January 2005) at a level of C1.1.  The  
current GEOS 12 measurement at 0927 UTC is  at X1.4 (GEOS 10 is recording  
X1.5), and still climbing.  This is a VERY long rise-time.  Most flares  
begin and end within minutes to at most a half-hour.

Updates when possible and if warranted will be issued.

73 de Tomas, NW7US (AAR0JA/AAA0WA)

: Propagation Editor for CQ, CQ VHF, Popular Communications :
: Creator; live propagation center http://prop.hfradio.org/ :
: Associate Member of Propagation Studies Committee of RSGB :
: US Army Miltary Affiliate Radio Service (MARS) SMD AAA0WA :
: 122.93W 47.67N / Brinnon, Washington USA CN87 CW/SSB/DIGI :
: Website/software/database design http://newwebmakers.com/ :
: 10x56526, FISTS 7055, FISTS NW 57, Lighthouse Society 144 :



-- 

73 de Tomas, NW7US (AAR0JA/AAA0WA)

: Propagation Editor for CQ, CQ VHF, Popular Communications :
: Creator; live propagation center http://prop.hfradio.org/ :
: Associate Member of Propagation Studies Committee of RSGB :
: US Army Miltary Affiliate Radio Service (MARS) SMD AAA0WA :
: 122.93W 47.67N / Brinnon, Washington USA CN87 CW/SSB/DIGI :
: Website/software/database design http://newwebmakers.com/ :
: 10x56526, FISTS 7055, FISTS NW 57, Lighthouse Society 144 :

---[Start Commercial]---------------------

World Radio TV Handbook 2005 is coming out. Preorder yours and support open communications for DXers:

http://www.amazon.com/exec/obidos/ASIN/0823077942/hardcoredxcom

---[End Commercial]-----------------------
________________________________________
Hard-Core-DX mailing list
Hard-Core-DX@xxxxxxxxxxxxxxxx
http://dallas.hard-core-dx.com/mailman/listinfo/hard-core-dx
http://www.hard-core-dx.com/
_______________________________________________

THE INFORMATION IN THIS ARTICLE IS FREE. It may be copied, distributed
and/or modified under the conditions set down in the Design Science License
published by Michael Stutz at http://dsl.org/copyleft/dsl.txt