:Product: 0204RSGA.txt :Issued: 2011 Feb 04 2200 UTC # Prepared jointly by the U.S. Dept. of Commerce, NOAA, # Space Weather Prediction Center and the U.S. Air Force. # Joint USAF/NOAA Report of Solar and Geophysical Activity SDF Number 035 Issued at 2200Z on 04 Feb 2011 IA. Analysis of Solar Active Regions and Activity from 03/2100Z to 04/2100Z: Solar activity was very low. Region 1152 (S18W01) produced a few B-class x-ray flares during the period. Newly numbered Region 1153 (N1518) remained stable and quiet. IB. Solar Activity Forecast: Solar activity is expected to be predominately very low with a chance for a C-class x-ray event for the next 3 days (5-7 February). IIA. Geophysical Activity Summary 03/2100Z to 04/2100Z: The geomagnetic field was predominately quiet with an isolated unsettled period between 04/03Z-04/06Z and an active period between 04/18Z and 04/21Z. A sudden impulse of 8 nT was observed at 04/0236Z in association with a reverse shock behind the slow moving CME from 30 January. Solar wind speeds reached near 500 km/s and Bz was sustained between -15 and -20 nT between 04/18Z and 04/21Z. IIB. Geophysical Activity Forecast: The geomagnetic field is forecast to be unsettled to active with a chance for an isolated minor storm early, then mostly quiet to unsettled for the second half of day 1 (5 February). Conditions are forecast to be predominately quiet on days 2 and 3 (6-7 February) as coronal hole effects wane. III. Event Probabilities 05 Feb-07 Feb Class M 01/01/01 Class X 01/01/01 Proton 01/01/01 PCAF Green IV. Penticton 10.7 cm Flux Observed 04 Feb 082 Predicted 05 Feb-07 Feb 082/082/082 90 Day Mean 04 Feb 084 V. Geomagnetic A Indices Observed Afr/Ap 03 Feb 000/001 Estimated Afr/Ap 04 Feb 010/010 Predicted Afr/Ap 05 Feb-07 Feb 008/008-005/005-005/005 VI. Geomagnetic Activity Probabilities 05 Feb-07 Feb A. Middle Latitudes Active 40/20/10 Minor storm 25/05/01 Major-severe storm 05/01/01 B. High Latitudes Active 50/20/10 Minor storm 20/10/01 Major-severe storm 10/01/01