:Product: Report of Solar-Geophysical Activity :Issued: 2010 Mar 25 2201 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 084 Issued at 2200Z on 25 Mar 2010 IA. Analysis of Solar Active Regions and Activity from 24/2100Z to 25/2100Z: Solar activity has been at very low levels for the past 24 hours. Region 1057 (N15E45) has shown steady growth in area (400 millionths) and is still classified as a D group. Several B-class flares were observed from Region 1057, the largest being a B7, optically uncorrelated event, at 25/0433Z. A far-sided CME was observed at 25/0128Z with an associated Type II radio sweep (shock velocity 1395 km/s), but does not look to be geoeffective. Region 1058 (N27W06) was numbered today and is classified as a simple A group. IB. Solar Activity Forecast: Solar activity is expected to be at very low to low levels. There is a chance for C-class flares from Region 1057. IIA. Geophysical Activity Summary 24/2100Z to 25/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind observations from the ACE spacecraft showed an increase of wind speed from 300 to 430 km/s following a rise in density (1 to 22 p/cc). These signatures are indicative of a co-rotating interactive region in advance of a weak coronal hole high-speed stream. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to remain at quiet to unsettled levels for day one (26 March) as the effects of the coronal hole high-speed stream subside. On day two (27 March), quiet levels are expected. On day three (28 March), the geomagnetic field is expected to be at quiet to unsettled levels as a new coronal hole high-speed stream becomes geoeffective. III. Event Probabilities 26 Mar-28 Mar Class M 05/05/05 Class X 01/01/01 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 25 Mar 088 Predicted 26 Mar-28 Mar 088/089/089 90 Day Mean 25 Mar 083 V. Geomagnetic A Indices Observed Afr/Ap 24 Mar 002/003 Estimated Afr/Ap 25 Mar 005/007 Predicted Afr/Ap 26 Mar-28 Mar 005/005-005/007-007/008 VI. Geomagnetic Activity Probabilities 26 Mar-28 Mar A. Middle Latitudes Active 20/05/20 Minor storm 01/01/05 Major-severe storm 01/01/01 B. High Latitudes Active 10/05/20 Minor storm 01/01/05 Major-severe storm 01/01/01