:Product: 20000519RSGA.txt :Issued: 2000 May 19 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 140 ISSUED AT 2200Z ON 19 MAY 2000 IA. ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM 18/2100Z TO 19/2100Z: ACTIVITY REMAINED AT MODERATE LEVELS BY VIRTUE OF AN OPTICALLY UNCORRELATED M1 AT 19/0058Z. REGIONS 8996 (S21W22), 8998 (S12W09), AND 9002 (N18E18) REMAINED LARGE REGIONS OF MODERATE MAGNETIC COMPLEXITY, BUT SHOWED NO SIGNIFICANT CHANGES. EACH PRODUCED OCCASIONAL C -CLASS SUBFLARES. THE REMAINING REGIONS WERE STABLE. NEW REGION 9011 (N19E69), AN H-TYPE GROUP TRAILING REGION 9010 (N20E57), ROTATED INTO VIEW DURING THE PERIOD. IB. SOLAR ACTIVITY FORECAST: SOLAR ACTIVITY IS EXPECTED TO REMAIN AT MODERATE LEVELS. REGIONS 8996, 8998, AND 9002 EACH APPEAR CAPABLE OF M-CLASS FLARE PRODUCTION. THERE IS ALSO A SLIGHT CHANCE FOR A MAJOR FLARE SOMETIME DURING THE PERIOD. IIA. GEOPHYSICAL ACTIVITY SUMMARY FROM 18/2100Z TO 19/2100Z: GEOMAGNETIC FIELD ACTIVITY REMAINED AT QUIET TO UNSETTLED LEVELS. IIB. GEOPHYSICAL ACTIVITY FORECAST: GEOMAGNETIC FIELD ACTIVITY IS EXPECTED TO RANGE FROM QUIET TO ACTIVE LEVELS. BRIEF ACTIVE LEVELS ARE POSSIBLE DURING THE PERIOD DUE TO CORONAL HOLE EFFECTS. III. EVENT PROBABILITIES 20 MAY-22 MAY CLASS M 80/80/80 CLASS X 15/15/15 PROTON 10/10/10 PCAF YELLOW IV. PENTICTON 10.7 CM FLUX OBSERVED 19 MAY 254 PREDICTED 20 MAY-22 MAY 260/260/265 90 DAY MEAN 19 MAY 194 V. GEOMAGNETIC A INDICES OBSERVED AFR/AP 18 MAY 008/010 ESTIMATED AFR/AP 19 MAY 012/008 PREDICTED AFR/AP 20 MAY-22 MAY 015/012-015/012-012/010 VI. GEOMAGNETIC ACTIVITY PROBABILITIES 20 MAY-22 MAY A. MIDDLE LATITUDES ACTIVE 30/30/25 MINOR STORM 15/15/10 MAJOR-SEVERE STORM 01/01/01 B. HIGH LATITUDES ACTIVE 35/35/30 MINOR STORM 20/20/15 MAJOR-SEVERE STORM 01/01/01