:Product: 20050527RSGA.txt
:Issued: 2005 May 27 2220 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 147 Issued at 2200Z on 27 May 2005
IA.  Analysis of Solar Active Regions and Activity from  26/2100Z
to 27/2100Z:  Solar activity was moderate. Region 767 (S08W02)
produced an M1/2f and associated tenflare at 27/1230 UTC. This
region also produced a C8 flare at 26/2139 UTC. A type IV radio
sweep was associated with this C8 event and a faint CME was observed
on LASCO imagery. Region 767 continues to develop in both size and
magnetic complexity, and is now nearing 400 millionths of white
light area.
IB.  Solar Activity Forecast:  Solar activity is expected to be low
to moderate. Region 767 has the potential for further M-class
activity. Old Region 758 (S10, L=139), a large and moderately
complex region during its last rotation, is due to rotate onto the
visible disk on 28 May.
IIA.  Geophysical Activity Summary 26/2100Z to 27/2100Z:
The geomagnetic field was quiet. The greater than 2 MeV electron flux
at geosynchronous orbit reached high levels again today.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to range from quiet to minor storming. A recurrent coronal
hole high speed stream is expected to rotate into geoeffective
position on 28 May. The most disturbed periods will likely occur on
29 and 30 May as the recent CMEs from Region 767 are expected to
impact the geomagnetic field.
III.  Event Probabilities 28 May-30 May
Class M    20/25/25
Class X    05/05/05
Proton     05/05/05
PCAF       green
IV.  Penticton 10.7 cm Flux
Observed           27 May 096
Predicted   28 May-30 May  100/105/110
90 Day Mean        27 May 091
V.  Geomagnetic A Indices
Observed Afr/Ap 26 May  001/004
Estimated Afr/Ap 27 May  005/008
Predicted Afr/Ap 28 May-30 May  015/020-020/020-015/015
VI.  Geomagnetic Activity Probabilities 28 May-30 May
A.  Middle Latitudes
Active                25/40/25
Minor storm           15/20/15
Major-severe storm    05/10/05
B.  High Latitudes
Active                40/50/40
Minor storm           20/30/20
Major-severe storm    10/15/10