Joint USAF/NOAA Report of Solar and Geophysical Activity 22 Aug 2004

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

Updated 2004 Aug 22 2210 UTC

Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 235 Issued at 2200Z on 22 Aug 2004

IA. Analysis of Solar Active Regions and Activity from 21/2100Z
to 22/2100Z: Solar activity continues to be very low. Minor B-class
activity was observed in Region 661 (N06W47). This region, which
still maintains over 400 millionths of white light area coverage, is
in a slow decay phase. With the exception of Region 665 (N04W15),
which was numbered today, all active regions were stable or in
decay.

IB. Solar Activity Forecast: Solar activity is expected to be very
low to low. There is a small chance of a C-class flare.

IIA. Geophysical Activity Summary 21/2100Z to 22/2100Z:
The geomagnetic field was quiet to active with isolated minor storm
periods. The disturbed periods are due to a slightly elevated solar
wind speed and a predominantly southward IMF Bz. The greater than 2
MeV electron flux at geosynchronous orbit was at high levels.

IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be quiet to active with isolated minor storm periods at
high latitudes.

III. Event Probabilities 23 Aug-25 Aug

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

IV. Penticton 10.7 cm Flux

• Observed 22 Aug 115
• Predicted 23 Aug-25 Aug 115/115/110
• 90 Day Mean 22 Aug 110

V. Geomagnetic A Indices

• Observed Afr/Ap 21 Aug 014/017
• Estimated Afr/Ap 22 Aug 015/015
• Predicted Afr/Ap 23 Aug-25 Aug 012/015-012/015-010/012

VI. Geomagnetic Activity Probabilities 23 Aug-25 Aug

A. Middle Latitudes

• Active 25/25/20
• Minor storm 10/10/05
• Major-severe storm 01/01/01

B. High Latitudes

• Active 35/35/25
• Minor storm 15/15/10
• Major-severe storm 05/05/01