:Product: 20020426RSGA.txt
:Issued: 2002 Apr 26 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 116 Issued at 2200Z on 26 Apr 2002
IA.  Analysis of Solar Active Regions and Activity from  25/2100Z
to 26/2100Z:  Solar activity was low with very isolated low C-class
activity observed. Region 9912 (N11W78) continues to slowly decay as
it approaches the west limb. Regions 9914 (N04W25), 9915 (N11W12),
and 9919 (N12E33), exhibited minor growth. The remaining regions on
the visible disk were stable or in decay. A significant segment of
the large E-W filament centered near S32W12 disappeared late in the
period. It is too early to confirm if a CME accompanied this
filament eruption.
IB.  Solar Activity Forecast:  Solar activity is expected to continue
at low levels. Isolated low c-class flares are expected.
IIA.  Geophysical Activity Summary 25/2100Z to 26/2100Z:
The geomagnetic field was quiet. The greater than 10 MeV proton event
that began on 21/0225Z, and peaked on 21/2320Z at 2520 pfu, ended
today at 26/0715Z. The 10 MeV proton flux remains elevated at near 5
pfu, but continues to slowly decline.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to become unsettled with isolated active periods. A
recurrent coronal hole is moving into a geoeffectively favorable
position; expect disturbed conditions to develop this period.
III.  Event Probabilities 27 Apr-29 Apr
Class M    25/25/25
Class X    05/05/05
Proton     01/01/01
PCAF       in progress
IV.  Penticton 10.7 cm Flux
Observed           26 Apr 163
Predicted   27 Apr-29 Apr  165/165/170
90 Day Mean        26 Apr 196
V.  Geomagnetic A Indices
Observed Afr/Ap 25 Apr  002/005
Estimated Afr/Ap 26 Apr  005/007
Predicted Afr/Ap 27 Apr-29 Apr  012/015-012/012-010/010
VI.  Geomagnetic Activity Probabilities 27 Apr-29 Apr
A.  Middle Latitudes
Active                35/35/30
Minor storm           15/15/10
Major-severe storm    05/05/01
B.  High Latitudes
Active                40/40/35
Minor storm           20/20/15
Major-severe storm    05/05/01