:Product: 0604RSGA.txt :Issued: 2011 Jun 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 155 Issued at 2200Z on 04 Jun 2011 IA. Analysis of Solar Active Regions and Activity from 03/2100Z to 04/2100Z: Solar activity was low. Region 1226 (S21W25) produced a C1 at 03/2242Z. This region remains a D-type group with a beta magnetic classification. All other numbered regions remained stable. No new regions were numbered today. IB. Solar Activity Forecast: Solar activity is expected to be low with a slight chance for a M-class event. IIA. Geophysical Activity Summary 03/2100Z to 04/2100Z: The geomagnetic field was quiet to active. The ACE spacecraft detected an interplanetary shock passage at 04/1958Z. Solar winds jumped from around 325 km/s to 455 km/s, density increased, and the IMF Bt went from 5nT to 20 nT. A geomagnetic sudden impulse was observed at 04/2045Z (54 nT) on the Boulder USGS magnetometer. This signature is consistent with the arrival of a CME. 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 mostly active with isolated minor storm conditions, and isolated major storming at high-latitudes, for day one (05 June). The source for the activity is a combination of continued CME effects, and the arrival of a geoeffective coronal hole high-speed stream. For day two (06 June) the geomagnetic field is expected to be quiet to unsettled with isolated active conditions. By day three (07 June) mostly quiet to unsettled levels are expected as the activity subsides. III. Event Probabilities 05 Jun-07 Jun Class M 10/10/10 Class X 05/05/05 Proton 01/01/01 PCAF green IV. Penticton 10.7 cm Flux Observed 04 Jun 103 Predicted 05 Jun-07 Jun 102/100/098 90 Day Mean 04 Jun 107 V. Geomagnetic A Indices Observed Afr/Ap 03 Jun 003/004 Estimated Afr/Ap 04 Jun 008/008 Predicted Afr/Ap 05 Jun-07 Jun 020/020-015/015-008/008 VI. Geomagnetic Activity Probabilities 05 Jun-07 Jun A. Middle Latitudes Active 40/30/15 Minor storm 20/10/05 Major-severe storm 05/01/01 B. High Latitudes Active 45/35/25 Minor storm 25/20/10 Major-severe storm 05/05/01