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Quick update:
At least an X10 or X11 class flare just occurred, peaking at 2049Z 29-X-2003, adding to the already dead HF conditions due to the CME passage and the Kp = 7. This one is a short-lived flare. Quick recovery is expected. I don't know, yet, what CME might be associated, if any. Details, soon. At the moment, most of the HF spectrum is "closed" to propagation, not because of the flare. I'm have not been hearing signals here in the Pacific Northwest on most of the HF, before the X11 flare. On many e-mail reflectors, I am reading some folks as saying, "Wow, that X17 flare sure has shut down the bands." Actually, it is not that solar flare that messed up the bands, today. Flares tend to cause radio blackouts that might last from a half hour to a number of hours. On the otherhand, major geomagnetic storms will cause HF radio propagation degradation because of "recombination." Today's general outage is due to the passage of one of the fastest moving coronal hole mass ejections on record. It caused the highest Kp index - a level 9 geomagnetic storm. Since it hit us, the Kp index has remained at or higher than 7. This is a severe geomagnetic storm. During a geomagnetic storm, the ionosphere experiences "recombination" - much like what happens at night. The maximum usable frequencies fall - sometime no HF propagation is possible, because the ionosphere is completely recombined... this is what is happening at this moment. Most of the HF spectrum is "shut down." Now, added to this geomagnetic storm and the general closure of the HF spectrum, we have this new X11-class flare from 2049Z. I don't yet know if a CME was associated with this one. More as details become available... 73 de Tomas, NW7US (AAR0JA/AAM0EWA) -- : Propagation Editor, CQ/CQ VHF/Popular Communications Magazines : : http://hfradio.org/ -- http://prop.hfradio.org/ -- Brinnon, WA : : 122.93W 47.67N - CW / SSB / DIGITAL / DX-Hunting / Propagation : : A creator of solutions -- http://accessnow.com/ -- Perl Rules! : : Washington State MARS Emergency Operations Officer - (AAM0EWA) : : WA State Army MARS Webmaster for http://wa.mars.hfradio.org/ : : 10x56526, FISTS 7055, FISTS NW 57, A.R. Lighthouse Society 144 : |
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