Joint USAF/NOAA Report of Solar and Geophysical Activity 23 Oct 2004

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

Updated 2004 Oct 23 2210 UTC

Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 297 Issued at 2200Z on 23 Oct 2004

IA. Analysis of Solar Active Regions and Activity from 22/2100Z
to 23/2100Z: Solar activity was low. A C9.9 flare occurred at
23/1654 UTC from Region 687 (N11E28). Region 687 also produced a
C8.0 flare at 23/1922 UTC. Region 682 (S13W73) produced a low level
C flare. New Region 691 (N16E69) was numbered today.

IB. Solar Activity Forecast: Solar activity is expected to be low
to moderate. Region 687 may produce isolated M-class activity.

IIA. Geophysical Activity Summary 22/2100Z to 23/2100Z:
The geomagnetic field was quiet.

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

III. Event Probabilities 24 Oct-26 Oct

• Class M 55/55/55
• Class X 05/05/05
• Proton 05/05/05
• PCAF Green

IV. Penticton 10.7 cm Flux

• Observed 23 Oct 132
• Predicted 24 Oct-26 Oct 130/130/130
• 90 Day Mean 23 Oct 104

V. Geomagnetic A Indices

• Observed Afr/Ap 22 Oct 005/006
• Estimated Afr/Ap 23 Oct 004/005
• Predicted Afr/Ap 24 Oct-26 Oct 005/005-010/012-010/008

VI. Geomagnetic Activity Probabilities 24 Oct-26 Oct

A. Middle Latitudes

• Active 15/20/20
• Minor storm 05/10/10
• Major-severe storm 01/05/05

B. High Latitudes

• Active 20/25/25
• Minor storm 10/15/15
• Major-severe storm 05/05/05