Joint USAF/NOAA Report of Solar and Geophysical Activity 15 Dec 2004

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

Updated 2004 Dec 15 2210 UTC

Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 350 Issued at 2200Z on 15 Dec 2004

IA. Analysis of Solar Active Regions and Activity from 14/2100Z
to 15/2100Z: Solar activity was very low. A B6.2 flare was observed
at 15/1108 UTC from a region on the east limb near S17. No new
regions were numbered today.

IB. Solar Activity Forecast: Solar activity is expected to be very
low to low.

IIA. Geophysical Activity Summary 14/2100Z to 15/2100Z:
The geomagnetic field was quiet.

IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be quiet to active on 16 and 17 December due to the
effects from a recurrent geoeffective coronal hole. Conditions are
expected to subside to quiet to unsettled on 18 December.

III. Event Probabilities 16 Dec-18 Dec

• Class M 01/01/01
• Class X 01/01/01
• Proton 01/01/01
• PCAF Green

IV. Penticton 10.7 cm Flux

• Observed 15 Dec 089
• Predicted 16 Dec-18 Dec 085/090/090
• 90 Day Mean 15 Dec 104

V. Geomagnetic A Indices

• Observed Afr/Ap 14 Dec 004/007
• Estimated Afr/Ap 15 Dec 005/004
• Predicted Afr/Ap 16 Dec-18 Dec 010/010-012/020-008/015

VI. Geomagnetic Activity Probabilities 16 Dec-18 Dec

A. Middle Latitudes

• Active 25/30/20
• Minor storm 10/15/10
• Major-severe storm 01/05/01

B. High Latitudes

• Active 30/35/25
• Minor storm 15/20/15
• Major-severe storm 05/10/05