:Product: 20030531RSGA.txt
:Issued: 2003 May 31 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 151 Issued at 2200Z on 31 May 2003
IA.  Analysis of Solar Active Regions and Activity from  30/2100Z
to 31/2100Z:  Solar activity was high. Region 365 (S07W72) produced
an M9/2b flare at 31/0224 UTC. The flare was accompanied by a 1300
sfu radio burst at 2695 MHz, a Type II radio sweep, and a CME
observed by the SOHO spacecraft to be directed mostly towards the
southwest. This region also generated a few C-class subflares during
the past day. Further decay, mostly in penumbral area, is evident
since yesterday.
IB.  Solar Activity Forecast:  Solar activity is expected to be
moderate to high. Region 365 may produce yet another major flare
before it passes the west solar limb.
IIA.  Geophysical Activity Summary 30/2100Z to 31/2100Z:
The geomagnetic field ranged from quiet to major storm levels. The
most disturbed period occurred from 31/0300-0600 UTC and has since
been quiet to unsettled at most locations. A greater than 10 MeV
proton event started at 31/0440 UTC, reached a 27 pfu peak at
31/0645 UTC, and ended at 31/1440 UTC.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to be mostly unsettled to active with a chance of isolated
storm conditions at local nighttime. The field may become
increasingly disturbed by 03 June due to a recurrent coronal hole
high-speed stream.
III.  Event Probabilities 01 Jun-03 Jun
Class M    80/50/10
Class X    20/10/01
Proton     20/10/01
PCAF       yellow
IV.  Penticton 10.7 cm Flux
Observed           31 May 113
Predicted   01 Jun-03 Jun  110/100/090
90 Day Mean        31 May 125
V.  Geomagnetic A Indices
Observed Afr/Ap 30 May  036/049
Estimated Afr/Ap 31 May  025/040
Predicted Afr/Ap 01 Jun-03 Jun  015/025-015/015-020/030
VI.  Geomagnetic Activity Probabilities 01 Jun-03 Jun
A.  Middle Latitudes
Active                20/15/30
Minor storm           10/05/05
Major-severe storm    05/01/01
B.  High Latitudes
Active                50/30/60
Minor storm           20/05/05
Major-severe storm    10/01/01