Report of Solar-Geophysical Activity
Issued: 2005 Aug 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 233 Issued at 2200Z on 21 Aug 2005 IA. Analysis of Solar Active Regions and Activity from 20/2100Z to 21/2100Z: Solar activity was low. Region 798 (S11W48) produced a single small c-class x-ray flare at 21/1019 UTC. The region remains the largest on the disk and has become more complex since yesterday.
IB. Solar Activity Forecast: Solar activity is expected to be low to moderate. Region 798 appears capable of an isolated M-class flare.
IIA. Geophysical Activity Summary 20/2100Z to 21/2100Z:
The geomagnetic field ranged from quiet to active. ACE real time solar wind data suggests the onset of a coronal hole high speed stream at about 21/1530 UTC. The greater than 2 MeV electron flux at geosynchronous orbit was high.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet to unsettled with isolated active periods under the influence of a high speed coronal hole stream.
III. Event Probabilities 22 Aug-24 Aug
Class M 20/20/20
Class X 05/05/05
Proton 05/05/05
PCAF green
IV. Penticton 10.7 cm Flux
Observed 21 Aug 099
Predicted 22 Aug-24 Aug 100/105/105
90 Day Mean 21 Aug 093
V. Geomagnetic A Indices
Observed Afr/Ap 20 Aug 002/005
Estimated Afr/Ap 21 Aug 010/010
Predicted Afr/Ap 22 Aug-24 Aug 012/015-012/015-012/010 VI. Geomagnetic Activity Probabilities 22 Aug-24 Aug A. Middle Latitudes
Active 30/30/30
Minor storm 15/15/15
Major-severe storm 05/05/05
B. High Latitudes
Active 50/50/50
Minor storm 20/20/20
Major-severe storm 05/05/05