Report of Solar-Geophysical Activity

Issued: 2006 Dec 06 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 340 Issued at 2200Z on 06 Dec 2006

IA. Analysis of Solar Active Regions and Activity from 05/2100Z to 06/2100Z: Solar activity was high. Region 930 (S05E60) produced an M6/SF flare at 06/0823Z and an X6/3B flare at 06/1847Z. The M6 flare had an associated Type IV radio sweep and a Tenflare. The X6 flare had an associated Type IV radio sweep, a Tenflare, and a Type II radio sweep (estimated shock speed of 827 km/s). A CME was probably associated with this event, but LASCO imagery is unavailable for confirmation. Region 930 is now classified as a Dkc group with an area of 490 millionths. It is magnetically complex, with an east-west inversion line and a Beta-Gamma-Delta configuration.

IB. Solar Activity Forecast: Solar activity is expected to be high.

Region 930 is expected to produce M-class flares and there is a good chance for further X-class activity.

IIA. Geophysical Activity Summary 05/2100Z to 06/2100Z:

The geomagnetic field ranged from unsettled to minor storm levels.

Solar wind speed has increased to approximately 600 km/s, indicating the onset of a coronal hole high speed stream. The greater than 10 MeV proton flux reached the event threshold of 10 pfu at 06/1555Z, with a maximum observed flux so far of 24 at 2100Z.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be unsettled to active on 07 - 08 December with a chance for periods of minor or major storm conditions due to the recurrent coronal hole high speed stream. Quiet to unsettled conditions are expected on 09 December. The greater than 10 MeV proton event is expected to continue for at least another 24 hours.

III. Event Probabilities 07 Dec-09 Dec

Class M 85/85/85

Class X 50/50/50

Proton 95/70/50

PCAF red

IV. Penticton 10.7 cm Flux

Observed 06 Dec 103

Predicted 07 Dec-09 Dec 105/105/105

90 Day Mean 06 Dec 080

V. Geomagnetic A Indices

Observed Afr/Ap 05 Dec 002/002

Estimated Afr/Ap 06 Dec 018/025

Predicted Afr/Ap 07 Dec-09 Dec 020/025-015/015-010/010 VI. Geomagnetic Activity Probabilities 07 Dec-09 Dec A. Middle Latitudes

Active 35/30/25

Minor storm 20/15/10

Major-severe storm 05/05/01

B. High Latitudes

Active 35/30/25

Minor storm 20/15/10

Major-severe storm 05/05/01