:Product: 20050526RSGA.txt
:Issued: 2005 May 26 2210 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 146 Issued at 2200Z on 26 May 2005
IA.  Analysis of Solar Active Regions and Activity from  25/2100Z
to 26/2100Z:  Solar activity was very low.  A long duration B7.5
flare occurred at 26/1420 UTC from Region 767 (S08E12).  A filament
eruption was associated with this event, followed by a full halo CME
on LASCO imagery.  The bulk of the CME, first seen at 26/1506 UTC,
was directed to the south west.  The plane of sky speed of the
ejecta was approximately 575 km/s.  At the time of issue, a C8 flare
was in progress in this region.  New sunspot development between the
leading and trailing spots have increased the size and complexity of
this active region.  New Region 768 (S08W48) was numbered today.
IB.  Solar Activity Forecast:  Solar activity is expected to be low. 
Region 767 has the potential for C-class activity with a small
chance for an M-class flare.  Old Region 758 (S10, L=139), which
produced three M-flares on its last rotation, is expected to rotate
onto the visible disk on 28 May.
IIA.  Geophysical Activity Summary 25/2100Z to 26/2100Z:
The geomagnetic field was quiet.  The greater than 2 MeV electron
flux at geosynchronous orbit was high today.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to be quiet to unsettled with occasional active periods on
27 and 28 May due to the effects of a coronal hole high speed
stream.  The full halo CME from 26 May is expected to cause active
to minor storm conditions on 29 May.
III.  Event Probabilities 27 May-29 May
Class M    05/05/05
Class X    01/01/01
Proton     01/01/01
PCAF       green
IV.  Penticton 10.7 cm Flux
Observed           26 May 090
Predicted   27 May-29 May  090/095/100
90 Day Mean        26 May 091
V.  Geomagnetic A Indices
Observed Afr/Ap 25 May  002/006
Estimated Afr/Ap 26 May  005/005
Predicted Afr/Ap 27 May-29 May  010/010-015/020-020/020
VI.  Geomagnetic Activity Probabilities 27 May-29 May
A.  Middle Latitudes
Active                20/25/40
Minor storm           10/15/20
Major-severe storm    01/05/10
B.  High Latitudes
Active                20/40/50
Minor storm           10/20/30
Major-severe storm    01/10/15