NOAA SEC Report of Solar-Geophysical Activity 13 Dec 2001

:Product: Report of Solar-Geophysical Activity
:Issued: 2001 Dec 13 2200 UT
# Prepared jointly by the U.S. Dept. of Commerce, NOAA,
#Space Environment Center and the U.S. Air Force.
#
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 347 Issued at 2200Z on 13 Dec 2001
IA.  Analysis of Solar Active Regions and Activity from  12/2100Z
to 13/2100Z:  Solar activity was high. Region 9733 (N14E04) produced
an X6.2/3b flare at 13/1430 UTC. This event also produced associated
Type II and IV radio sweeps and a partial-halo coronal mass ejection
(CME). This region is continuing to grow more complex, developing a
near horizontal inversion line in its trailing portions. Region 9727
(S21W66) was also quite active during the period, producing three
M-class flares. Region 9727 showed continued growth in size and
complexity during the period. Regions 9727 and 9733 both retain
beta-gamma-delta magnetic classifications. Three new spot groups
were numbered today: 9739 (S13W02), 9740 (S06E56), and 9741
(N07E72).
IB.  Solar Activity Forecast:  Solar activity is expected to be at
moderate to high levels with isolated M-class flares likely. There
will also be a chance for a major flare from Regions 9727 or 9733.
IIA.  Geophysical Activity Summary 12/2100Z to 13/2100Z:
The geomagnetic field was at mostly quiet levels, with an isolated
unsettled period at 12/21-2400 UTC.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to be at quiet to unsettled conditions on the first day of
the forecast period. The CME produced by the X6.2 flare should
impact earth late on the second day. The impact is expected to
produce active conditions on the second and third days. Imagery from
the LASCO/SOHO spacecraft show that most of the CME is directed in a
predominately Northerly direction, hence the expected effect on
Earth should be significantly less than if the CME was more directly
aimed toward Earth.
III.  Event Probabilities 14 Dec-16 Dec
Class M    80/80/70
Class X    20/20/15
Proton     20/20/15
PCAF       yellow
IV.  Penticton 10.7 cm Flux
Observed           13 Dec 220
Predicted   14 Dec-16 Dec  220/220/210
90 Day Mean        13 Dec 218
V.  Geomagnetic A Indices
Observed Afr/Ap 12 Dec  008/012
Estimated Afr/Ap 13 Dec  006/007
Predicted Afr/Ap 14 Dec-16 Dec  012/015-020/020-025/025
VI.  Geomagnetic Activity Probabilities 14 Dec-16 Dec
A.  Middle Latitudes
Active                20/30/40
Minor storm           10/20/25
Major-severe storm    01/10/15
B.  High Latitudes
Active                25/40/45
Minor storm           15/25/30
Major-severe storm    05/10/10