Report of Solar-Geophysical Activity

Issued: 2005 Dec 12 2200 UTC

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

Joint USAF/NOAA Report of Solar and Geophysical Activity SDF Number 346 Issued at 2200Z on 12 Dec 2005 IA. Analysis of Solar Active Regions and Activity from 11/2100Z to 12/2100Z: Solar activity was very low. Today's activity consisted of a few B-class flares, all from Region 835 (N20E40). Region 835 showed some development of spots between the trailing and leading parts of the group, but decayed in total area. The level of activity in the region has been noticeably diminished since about 0300Z.

IB. Solar Activity Forecast: Solar activity is expected to be very low to low for the next three days (13-15 December).

IIA. Geophysical Activity Summary 11/2100Z to 12/2100Z:

The geomagnetic field was mostly quiet, with the exception of a period of unsettled to active levels between 0300-0600Z.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet to unsettled for 13 December and should be predominantly quiet for 14-15 December.

III. Event Probabilities 13 Dec-15 Dec

Class M 05/05/05

Class X 01/01/01

Proton 01/01/01

PCAF green

IV. Penticton 10.7 cm Flux

Observed 12 Dec 088

Predicted 13 Dec-15 Dec 090/090/090

90 Day Mean 12 Dec 085

V. Geomagnetic A Indices

Observed Afr/Ap 11 Dec 010/022

Estimated Afr/Ap 12 Dec 008/008

Predicted Afr/Ap 13 Dec-15 Dec 005/010-005/005-005/005 VI. Geomagnetic Activity Probabilities 13 Dec-15 Dec A. Middle Latitudes

Active 20/20/20

Minor storm 10/10/10

Major-severe storm 01/01/01

B. High Latitudes

Active 25/25/25

Minor storm 10/10/10

Major-severe storm 01/01/01