Report of Solar-Geophysical Activity

Issued: 2005 Nov 27 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 331 Issued at 2200Z on 27 Nov 2005 IA. Analysis of Solar Active Regions and Activity from 26/2100Z to 27/2100Z: Solar activity levels were very low. There are just two small sunspot groups on the visible disk. Region 824 (S14W20) is a small bipolar sunspot group that has shown no significant change over the past 24 hours. Region 825 (S03W10) is a small decaying alpha spot group. No significant activity was observed on the solar disk or limb.

IB. Solar Activity Forecast: Solar activity is expected to continue at very low levels. Isolated B-class flares are possible from Region 824. Two new small active regions are rotating into view on the east limb, which may slightly boost activity levels.

IIA. Geophysical Activity Summary 26/2100Z to 27/2100Z:

The geomagnetic field was quiet. Solar wind speed gradually increased from 320 km/s to near 420 km/s by the end of the period. The greater than 2 MeV electron flux at geosynchronous orbit was a high levels again today.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet to unsettled with isolated active periods.

III. Event Probabilities 28 Nov-30 Nov

Class M 01/01/01

Class X 01/01/01

Proton 01/01/01

PCAF green

IV. Penticton 10.7 cm Flux

Observed 27 Nov 081

Predicted 28 Nov-30 Nov 080/080/080

90 Day Mean 27 Nov 084

V. Geomagnetic A Indices

Observed Afr/Ap 26 Nov 008/005

Estimated Afr/Ap 27 Nov 005/005

Predicted Afr/Ap 28 Nov-30 Nov 008/010-005/010-010/015 VI. Geomagnetic Activity Probabilities 28 Nov-30 Nov A. Middle Latitudes

Active 15/15/25

Minor storm 05/05/15

Major-severe storm 01/01/01

B. High Latitudes

Active 25/25/30

Minor storm 15/15/20

Major-severe storm 05/05/10