:Product: 19970409RSGA.txt :Issued: 1997 Apr 09 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 099 ISSUED AT 2200Z ON 09 APR 1997 IA. ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM 08/2100Z TO 09/2100Z: SOLAR ACTIVITY WAS LOW BY VIRTUE OF A SINGLE C1 X-RAY BURST IN REGION 8026 (S23W91) IN CONJUNCTION WITH A BRIGHT SURGE ON THE LIMB. THIS REGION HAS ROTATED OFF THE WEST LIMB. REGION 8027 (S28W13) IS STILL DECAYING AND IS NOW A SIMPLE BXO SPOT GROUP. NEW REGION 8029 (N24W19), A CRO SPOT GROUP,WAS NUMBERED TODAY. IB. SOLAR ACTIVITY FORECAST: SOLAR ACTIVITY IS FORECAST TO BE VERY LOW TO LOW. REGION 8027 STILL HAS A DIMINISHED CHANCE OF C-CLASS ACTIVITY. REGION 8029 HAS POTENTIAL FOR C-CLASS ACTIVITY AS WELL. IIA. GEOPHYSICAL ACTIVITY SUMMARY FROM 08/2100Z TO 09/2100Z: THE GEOMAGNETIC FIELD HAS BEEN QUIET AT ALL LATITUDES. IIB. GEOPHYSICAL ACTIVITY FORECAST: THE GEOMAGNETIC FIELD IS EXPECTED TO BE UNSETTLED TO ACTIVE FOR THE FIRST DAY OF THE FORECAST AND MOSTLY ACTIVE ON DAY TWO IN RESPONSE TO THE C6/3N FLARE AND CME IN REGION 8027 ON 7 APRIL. HIGH LATITUDE STATIONS MAY EXPERIENCE MINOR STORMING WITH ISOLATED PERIODS OF MAJOR STORMING OVER THE NEXT TWO DAYS. ACTIVITY IS EXPECTED TO DIMINISH TO UNSETTLED LEVELS BY DAY THREE. III. EVENT PROBABILITIES 10 APR-12 APR CLASS M 05/01/01 CLASS X 01/01/01 PROTON 01/01/01 PCAF GREEN IV. PENTICTON 10.7 CM FLUX OBSERVED 09 APR 078 PREDICTED 10 APR-12 APR 076/076/076 90 DAY MEAN 09 APR 074 V. GEOMAGNETIC A INDICES OBSERVED AFR/AP 08 APR 005/004 ESTIMATED AFR/AP 09 APR 006/010 PREDICTED AFR/AP 10 APR-12 APR 015/030-020/025-010/012 VI. GEOMAGNETIC ACTIVITY PROBABILITIES 10 APR-12 APR A. MIDDLE LATITUDES ACTIVE 30/30/15 MINOR STORM 20/20/10 MAJOR-SEVERE STORM 10/10/05 B. HIGH LATITUDES ACTIVE 30/30/30 MINOR STORM 20/20/20 MAJOR-SEVERE STORM 10/10/10