:Product: 20030530RSGA.txt :Issued: 2003 May 30 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 150 Issued at 2200Z on 30 May 2003 IA. Analysis of Solar Active Regions and Activity from 29/2100Z to 30/2100Z: Solar activity was low. Region 365 (S07W59) remains the largest and most complex sunspot group on the disk with some decay evident since yesterday. The largest flare in this region was a C8/1n at 30/0650 UTC. IB. Solar Activity Forecast: Solar activity is expected to moderate to high. Region 365 remains capable of another major flare. IIA. Geophysical Activity Summary 29/2100Z to 30/2100Z: The geomagnetic field ranged from unsettled to severe storm levels. The field was mostly unsettled to active since about 30/0600 UTC with a single minor storm period from 30/1500-1800 UTC. The CME associated with the X1 flare early on 29 May was apparently observed to encounter the ACE spacecraft at about 30/1600 UTC. The shock in solar wind parameters was not strong and an SI was not clearly observed by ground magnetometers. The proton event at greater than 10 MeV has ended: 28/2335 UTC start, 121 pfu peak at 29/1530 UTC, and 30/0110 UTC end. IIB. Geophysical Activity Forecast: The geomagnetic field is expected to range from unsettled to minor storm levels as the current CME passes. III. Event Probabilities 31 May-02 Jun Class M 80/80/80 Class X 20/20/20 Proton 20/20/20 PCAF yellow IV. Penticton 10.7 cm Flux Observed 30 May 117 Predicted 31 May-02 Jun 115/110/105 90 Day Mean 30 May 125 V. Geomagnetic A Indices Observed Afr/Ap 29 May 059/089 Estimated Afr/Ap 30 May 035/060 Predicted Afr/Ap 31 May-02 Jun 025/040-015/025-015/020 VI. Geomagnetic Activity Probabilities 31 May-02 Jun A. Middle Latitudes Active 40/20/15 Minor storm 30/10/05 Major-severe storm 15/05/01 B. High Latitudes Active 20/50/50 Minor storm 50/20/10 Major-severe storm 30/10/01