:Product: 20021221RSGA.txt
:Issued: 2002 Dec 21 2200 UTC
# 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 355 Issued at 2200Z on 21 Dec 2002
IA.  Analysis of Solar Active Regions and Activity from  20/2100Z
to 21/2100Z:  Solar activity was at low levels.  Region 226 (S28W54)
produced most of today's observed activity, a C4.6/1f occurring at
21/0453 UTC was the largest flare during the period.  The
beta-gamma-delta magnetic structure remains intact although much
decay was noted in spot groups areal coverage today.  Region 229
(N19W29) continues to show steady decay and was fairly quiescent
today.  Region 230 (S08E06) underwent little change but remains a
beta-gamma magnetic complex.  Region 232 (N13W08) was newly assigned
today.
IB.  Solar Activity Forecast:  Solar activity is expected to be at
low to moderate levels.  Regions 226 and 230 are capable of
producing M-class flare activity.
IIA.  Geophysical Activity Summary 20/2100Z to 21/2100Z:
The geomagnetic field was predominantly at quiet to active levels as
the geoeffective coronal hole high speed stream wanes.  Middle and
high latitudes experienced storming conditions between 21/0300 and
0600 UTC.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to be at active to minor storm levels for day one of the
forecast period.  The CME from the M2.7 flare late on 19 December is
expected to arrive early to mid-day on 22 December.  Predominantly
quiet to unsettled conditions are expected on days two and three.
III.  Event Probabilities 22 Dec-24 Dec
Class M    50/50/50
Class X    10/10/10
Proton     05/05/05
PCAF       yellow
IV.  Penticton 10.7 cm Flux
Observed           21 Dec 184
Predicted   22 Dec-24 Dec  185/180/180
90 Day Mean        21 Dec 167
V.  Geomagnetic A Indices
Observed Afr/Ap 20 Dec  012/016
Estimated Afr/Ap 21 Dec  015/018
Predicted Afr/Ap 22 Dec-24 Dec  025/025-012/015-006/010
VI.  Geomagnetic Activity Probabilities 22 Dec-24 Dec
A.  Middle Latitudes
Active                35/20/15
Minor storm           25/10/01
Major-severe storm    10/05/01
B.  High Latitudes
Active                40/30/20
Minor storm           30/15/05
Major-severe storm    15/10/01