:Product: 20020521RSGA.txt
:Issued: 2002 May 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 141 Issued at 2200Z on 21 May 2002
IA.  Analysis of Solar Active Regions and Activity from  20/2100Z
to 21/2100Z:  Solar activity was low during the past 24 hours.
Today's largest event was a C4/Sf from Region 9960 (N14E35). A
comparison of white light and magnetogram data indicate that this
region has a small delta configuration. Region 9961 (N14E35)  also
produced some C-class subflares today and shows a compact delta in
the leading part of the group. Region 9957 (N09E08) continues to be
the largest group on the disk and also possesses a delta. However,
this region was quiet and stable today, and is beginning to show
signs of decay.
IB.  Solar Activity Forecast:  Solar activity is expected to be
moderate during the next three days. The most likely sources for
energetic flare activity are 9957 and 9961, although 9960 could
contribute an isolated M-class event. There is a slight chance for
an X-class flare or proton producing event.
IIA.  Geophysical Activity Summary 20/2100Z to 21/2100Z:
The geomagnetic field was mostly quiet to unsettled. There was one
period of active conditions from 0600-0900 UTC at high latitudes.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to be predominantly quiet to unsettled for the next three
days. There is a slight chance for some isolated active  periods on
day two (due to the CME of 19/2026 UTC) and on day three due to
possible coronal hole effects.
III.  Event Probabilities 22 May-24 May
Class M    70/70/70
Class X    20/20/20
Proton     15/15/15
PCAF       yellow
IV.  Penticton 10.7 cm Flux
Observed           21 May 186
Predicted   22 May-24 May  180/180/175
90 Day Mean        21 May 184
V.  Geomagnetic A Indices
Observed Afr/Ap 20 May  008/014
Estimated Afr/Ap 21 May  008/010
Predicted Afr/Ap 22 May-24 May  005/010-012/012-012/010
VI.  Geomagnetic Activity Probabilities 22 May-24 May
A.  Middle Latitudes
Active                20/25/35
Minor storm           10/15/15
Major-severe storm    05/10/10
B.  High Latitudes
Active                20/20/25
Minor storm           10/20/35
Major-severe storm    05/20/10