:Product: 0504RSGA.txt :Issued: 2011 May 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 124 Issued at 2200Z on 04 May 2011 IA. Analysis of Solar Active Regions and Activity from 03/2100Z to 04/2100Z: Solar activity has been very low during the past 24 hours. Region 1204 (N17E13) produced a B9 x-ray event at 04/0144Z. An eruptive filament was observed in the vicinity of Region 1205 (N14E23) at 04/1656Z. The remaining active regions were quiet and stable. IB. Solar Activity Forecast: Solar activity is expected to be very low to low during days one through three (05-07 May). IIA. Geophysical Activity Summary 03/2100Z to 04/2100Z: The geomagnetic field has been quiet during the past 24 hours. Observations from the ACE spacecraft indicate a steady decrease in solar wind velocity from 600 km/s to around 425 km/s as the recent coronal hole high speed stream subsided. The greater than 2 MeV electron flux at geosynchronous orbit was at high levels throughout the period. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be predominately quiet with isolated unsettled periods for days one through three (05-07 May). III. Event Probabilities 05 May-07 May Class M 01/01/01 Class X 01/01/01 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 04 May 107 Predicted 05 May-07 May 107/110/110 90 Day Mean 04 May 109 V. Geomagnetic A Indices Observed Afr/Ap 03 May 008/013 Estimated Afr/Ap 04 May 006/008 Predicted Afr/Ap 05 May-07 May 005/005-005/005-007/007 VI. Geomagnetic Activity Probabilities 05 May-07 May A. Middle Latitudes Active 05/05/10 Minor storm 01/01/01 Major-severe storm 01/01/01 B. High Latitudes Active 10/10/15 Minor storm 05/05/10 Major-severe storm 01/01/01