:Product: 20021225RSGA.txt
:Issued: 2002 Dec 25 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 359 Issued at 2200Z on 25 Dec 2002
IA.  Analysis of Solar Active Regions and Activity from  24/2100Z
to 25/2100Z:  Solar activity was at low levels.  The largest event
was an optically uncorrelated C4.8 flare at 25/0546 UTC.  Two of the
most active regions over the past week, Region 224 (S14W92) and
Region 226 (S28, L=122), rotated beyond the west limb today.  Region
230 (S08W50) continues to decay and has lost its trailing spots.
The region is now a simple Hax spot group with an alpha magnetic
configuration.  New Region 235 (N13E28) was numbered today.
IB.  Solar Activity Forecast:  Solar activity is expected to be low.
IIA.  Geophysical Activity Summary 24/2100Z to 25/2100Z:
The geomagnetic field was predominantly at unsettled levels.  One
period of isolated active conditions occurred.  Solar wind velocity
gradually decreased throughout the day from 540 km/s to 440 km/s and
Bz was slightly negative for most of the day.  The greater than 2
MeV electron flux at geo-synchronous orbit reached high levels
today.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to be quiet to active.  A large positive polarity coronal
hole will rotate into a geo-effective position on day two of the
period.  Unsettled to active conditions are expected for day two and
day three.
III.  Event Probabilities 26 Dec-28 Dec
Class M    20/20/15
Class X    01/01/01
Proton     01/01/01
PCAF       green
IV.  Penticton 10.7 cm Flux
Observed           25 Dec 132
Predicted   26 Dec-28 Dec  130/125/120
90 Day Mean        25 Dec 167
V.  Geomagnetic A Indices
Observed Afr/Ap 24 Dec  014/018
Estimated Afr/Ap 25 Dec  012/015
Predicted Afr/Ap 26 Dec-28 Dec  010/015-015/018-020/025
VI.  Geomagnetic Activity Probabilities 26 Dec-28 Dec
A.  Middle Latitudes
Active                10/20/30
Minor storm           01/10/15
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/25/35
Minor storm           05/10/20
Major-severe storm    01/05/10