Report of Solar-Geophysical Activity

Issued: 2005 Dec 24 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 358 Issued at 2200Z on 24 Dec 2005 IA. Analysis of Solar Active Regions and Activity from 23/2100Z to 24/2100Z: Solar activity was very low. New Regions 840 (S03E66) and 841 (N04E74) were numbered today.

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

IIA. Geophysical Activity Summary 23/2100Z to 24/2100Z:

The geomagnetic field was quiet.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet to unsettled on 25 and 26 December. On 27 December, active to minor storm periods are possible due to a coronal hole high speed stream moving into geoeffective position.

III. Event Probabilities 25 Dec-27 Dec

Class M 10/10/10

Class X 01/01/01

Proton 01/01/01

PCAF green

IV. Penticton 10.7 cm Flux

Observed 24 Dec 092

Predicted 25 Dec-27 Dec 090/085/085

90 Day Mean 24 Dec 084

V. Geomagnetic A Indices

Observed Afr/Ap 23 Dec 001/001

Estimated Afr/Ap 24 Dec 004/007

Predicted Afr/Ap 25 Dec-27 Dec 005/010-005/007-010/010 VI. Geomagnetic Activity Probabilities 25 Dec-27 Dec A. Middle Latitudes

Active 15/15/25

Minor storm 05/05/10

Major-severe storm 01/01/05

B. High Latitudes

Active 25/20/25

Minor storm 10/10/10

Major-severe storm 05/01/05