Our latest severe (Kp-8) to extreme (Kp-9) geomagnetic storm has come to an
end. Unfortunately though the very fast moving (1000+ k/s) partial halo coronal
mass ejection released by sunspot group #10696 on November 10th will arrive on
UTC November 11-12, 2004 and create another strong (Kp-7) to severe (Kp-8)
geomagnetic storm. An extreme (Kp-9) storm is less likely this time around as
part of the CME will miss Earth.
Fortunately sunspot group #10696 will be rotating around the west limb within
24 hours and space weather and geomagnetic activity should slowly return to
normal levels. It will take another two days for the current elevated energetic
proton storm >10 mev to end so in the interim we can expect a continuation of
some high latitude propagation path absorption on the MF AM broadcast band, 160
and 120 meters. we can also expect mid and lower latitude LF/MF propagation
paths to stay depressed for a while until the geomagnetic equatorial ring
current unloads it's cache of precipitated electrons. The DST index is a
measuring gauge so to speak for the equatorial ring current. You can see the
current DST index at:
http://swdcdb.kugi.kyotou.ac.jp/dstdir/dst1/q/Dstqthism.html .
Also normally a Boulder K index of 9 is needed for low latitude visible aurora
in the U.S. and this time around the Boulder K only reached an 8. But I would
still be interested in getting any reports of visible aurora south of 30 deg.
N/S latitude. Remember though that visible aurora is not automatic with
geomagnetic storming. The magnetic (Bz) component of the solar wind must be a
negative value in nt (nano tesla's) in unison with a geomagnetic storm for
aurora to be seen.
73,
Thomas F. Giella, KN4LF
Retired Space & Atmospheric Weather Forecaster
Plant City, FL, USA
Grid Square EL87WX
Lat & Long 27 58 33.6397 N 82 09 52.4052 W
kn4lf@arrl.net
Propagation eGroup: http://lists.contesting.com/mailman/listinfo/propagation
PropNET Beacon Program: http://www.propnet.org
KN4LF Daily Solar Space Weather & Geomagnetic Data Archive:
http://www.kn4lf.com/kn4lf5.htm
KN4LF HF/MF Frequency Radio Propagation Theory Notes:
http://www.kn4lf.com/kn4lf8.htm
KN4LF Amateur & SWL Radio History: http://www.kn4lf.com/index.htm
----- Original Message -----
From: Solar Influences Data analysis Center
Sent: Thursday, November 11, 2004 9:10 AM
Subject: SIDC Ursigram
:Issued: 2004 Nov 11 1407 UTC
:Product: documentation at http://sidc.oma.be/products/meu
#------------------------------------------------------------------------------#
# DAILY BULLETIN ON SOLAR AND GEOMAGNETIC ACTIVITY from the SIDC (RWC-Belgium) #
#------------------------------------------------------------------------------#
SIDC URSIGRAM 41111
SIDC SOLAR BULLETIN 11 Nov 2004, 1402UT
SIDC FORECAST (valid from 1230UT, 11 Nov 2004 until 13 Nov 2004)
SOLAR FLARES : Eruptive (C-class flares expected, probability >= 50%)
GEOMAGNETISM : Severe geomagnetic storm expected (A>=100 or K>=7)
SOLAR PROTONS : Proton event in progress (>10 MeV)
PREDICTIONS FOR 11 Nov 2004 10CM FLUX: 104 / AP: 025
PREDICTIONS FOR 12 Nov 2004 10CM FLUX: 096 / AP: 059
PREDICTIONS FOR 13 Nov 2004 10CM FLUX: 090 / AP: 011
COMMENT: The magnetic storm is now declining and active or minor storm
conditions are now observed. The solar wind speed has now decreased to 600km/s
and Bz remains near 0. For a few hours, we thus expect unsettled to active
geomagnetic conditions. However, the halo CME associated with the Nov. 10 X2.5
flare is expected to hit the magnetosphere late today Nov. 11 or early on Nov.
12. and to induce a major or severe magnetic storm. The magnetosphere should
become quiet again on Nov. 13. The source region, #61 (NOAA686), has been
steadily declining over the last 3 days, and no significant flare occurred after
the Nov. 10 X flare. However, it keeps a beta-gamma-delta magnetic configuration
and can still produce M flares and an isolated X flare before disappearing at
the West limb tomorrow, Nov. 12.
SOLAR INDICES FOR 10 Nov 2004
SUNSPOT INDEX : 057
10CM SOLAR FLUX : 105
AK CHAMBON LA FORET : 145
AK WINGST : ///
ESTIMATED AP : 121
NOTICEABLE EVENTS SUMMARY
DAY BEGIN MAX END LOC XRAY OP 10CM RADIO BURST TYPES Catania NOAA NOTE
NONE
---
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