Joint USAF/NOAA Report of Solar and Geophysical Activity 27 Dec 2004

Prepared jointly by the U.S. Dept. of Commerce, NOAA,
Space Environment Center and the U.S. Air Force.
Updated 2004 Dec 27 2200 UTC

Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 362 Issued at 2200Z on 27 Dec 2004

IA. Analysis of Solar Active Regions and Activity from 26/2100Z
to 27/2100Z: Solar activity was very low. Several small B-class
flares were produced by Region 713 (S09W65) and a region on the
northeast limb.

IB. Solar Activity Forecast: Solar activity is expected to be very
low with a chance for isolated C-class activity from Region 713.

IIA. Geophysical Activity Summary 26/2100Z to 27/2100Z:
The geomagnetic field was quiet to unsettled.

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

III. Event Probabilities 28 Dec-30 Dec

• Class M 05/05/05
• Class X 01/01/01
• Proton 01/01/01
• PCAF green

IV. Penticton 10.7 cm Flux

• Observed 27 Dec 097
• Predicted 28 Dec-30 Dec 100/095/095
• 90 Day Mean 27 Dec 104

V. Geomagnetic A Indices

• Observed Afr/Ap 26 Dec 009/010
• Estimated Afr/Ap 27 Dec 008/009
• Predicted Afr/Ap 28 Dec-30 Dec 006/008-005/005-005/005

VI. Geomagnetic Activity Probabilities 28 Dec-30 Dec

A. Middle Latitudes

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

B. High Latitudes

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