Report of Solar-Geophysical Activity
Issued: 2005 Aug 22 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 234 Issued at 2200Z on 22 Aug 2005 IA. Analysis of Solar Active Regions and Activity from 21/2100Z to 22/2100Z: Solar activity was high. Region 798 (S11W62) produced an M5/1n at 22/1727 UTC. This flare was associated with significant radio output that included a 7100 sfu burst at 2695 MHz, 22000 sfu at 245 MHz, and type IV sweep activity. This region also produced an M2/1f flare at 22/0133 UTC that included significant radio output.
Both flares were associated with apparent earth-directed CMEs.
IB. Solar Activity Forecast: Solar activity is expected to be moderate. Another major flare is possible in Region 798.
IIA. Geophysical Activity Summary 21/2100Z to 22/2100Z:
The geomagnetic field was quiet to unsettled with isolated active periods. This activity is believed to be the result of a high-speed coronal hole stream. The greater than 10 MeV proton flux passed the 10 pfu event threshold at 22/2040 UTC. This event resulted from the M5 flare discussed in Part IA. Today's observed Penticton 10.7 flux was flare enhanced. The daily background value reported in Part IV was estimated to be 105 sfu.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet to unsettled with isolated active periods for the next 24 hours. Storm conditions are possible on Aug 24 and 25 due to the CME activity which occurred today. The greater than 10 MeV proton event is expected to continue for the next 24 hours.
III. Event Probabilities 23 Aug-25 Aug
Class M 30/30/30
Class X 05/05/05
Proton 80/20/10
PCAF red
IV. Penticton 10.7 cm Flux
Observed 22 Aug 157
Predicted 23 Aug-25 Aug 105/105/100
90 Day Mean 22 Aug 094
V. Geomagnetic A Indices
Observed Afr/Ap 21 Aug 005/008
Estimated Afr/Ap 22 Aug 010/012
Predicted Afr/Ap 23 Aug-25 Aug 010/010-020/025-020/035 VI. Geomagnetic Activity Probabilities 23 Aug-25 Aug A. Middle Latitudes
Active 30/50/50
Minor storm 15/20/20
Major-severe storm 01/05/05
B. High Latitudes
Active 50/60/60
Minor storm 15/25/25
Major-severe storm 05/10/10