Joint USAF/NOAA Report of Solar and Geophysical Activity 20 Aug 2005

Prepared jointly by the U.S. Dept. of Commerce, NOAA,
Space Environment Center and the U.S. Air Force.

Updated 2005 Aug 20 2203 UTC

Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 232 Issued at 2200Z on 20 Aug 2005

IA. Analysis of Solar Active Regions and Activity from 19/2100Z
to 20/2100Z: Solar activity was very low. Only small B-class flares
occurred. Region 798 (S11W33) remains the largest sunspot group on
the visible disk and has continued to grow in size and complexity.
Region 801 (N06E54) was numbered.

IB. Solar Activity Forecast: Solar activity is expected to be very
low to low. Most activity is expected in Region 798.

IIA. Geophysical Activity Summary 19/2100Z to 20/2100Z:
The geomagnetic field was quiet to unsettled. The greater than 2 MeV
electron flux at geosynchronous orbit remained high.

IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be mostly quiet.

III. Event Probabilities 21 Aug-23 Aug

• Class M 10/10/10
• Class X 01/01/01
• Proton 01/01/01
• PCAF green

IV. Penticton 10.7 cm Flux

• Observed 20 Aug 098
• Predicted 21 Aug-23 Aug 100/100/105
• 90 Day Mean 20 Aug 093

V. Geomagnetic A Indices

• Observed Afr/Ap 19 Aug 006/007
• Estimated Afr/Ap 20 Aug 005/007
• Predicted Afr/Ap 21 Aug-23 Aug 005/005-005/005-010/010

VI. Geomagnetic Activity Probabilities 21 Aug-23 Aug

A. Middle Latitudes

• Active 15/15/15
• Minor storm 05/05/05
• Major-severe storm 01/01/01

B. High Latitudes

• Active 30/30/30
• Minor storm 10/10/10
• Major-severe storm 01/01/01