:Product: Report of Solar-Geophysical Activity :Issued: 2000 Mar 20 2200 UT # 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 080 ISSUED AT 2200Z ON 20 MAR 2000 IA. ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM 19/2100Z TO 20/2100Z: SOLAR ACTIVITY REMAINED MODERATE. REGION 8910 (N13W35) PRODUCED AN M2/2B FLARE AT 1644Z. THE REGION HAD NUMEROUS SMALLER EVENTS AS IT REMAINED LARGE (680 MILLIONTHS IN WHITE LIGHT) AND COMPLEX (BETA-GAMMA DELTA). EARLIER IN THE DAY, AN M2/LIMB FLARE WITH TYPES II AND IV SWEEP OCCURRED AT 0834Z, FROM AN AREA NEAR S18E90. NEWLY ASSIGNED REGION 8921 (S15E71) IS NEARBY, BUT LIMB PROXIMITY PROHIBITS AN UNAMBIGUOUS DETERMINATION OF THE SOURCE OF THAT ACTIVITY. SOHO DATA SUGGEST THERE MAY BE MULTIPLE ACTIVE REGIONS COMING INTO VIEW THERE. ELSEWHERE, A SECOND NEW REGION, 8920 (N24E55), WAS NUMBERED. IB. SOLAR ACTIVITY FORECAST: SOLAR ACTIVITY SHOULD REMAIN MODERATE. REGION 8910 IS LIKELY TO PRODUCE M-CLASS EVENTS, WITH A CHANCE OF AN ISOLATED X-CLASS FLARE. IIA. GEOPHYSICAL ACTIVITY SUMMARY FROM 19/2100Z TO 20/2100Z: THE GEOMAGNETIC FIELD WAS QUIET TO UNSETTLED. IIB. GEOPHYSICAL ACTIVITY FORECAST: THE GEOMAGNETIC FIELD IS EXPECTED TO PERSIST AT QUIET TO UNSETTLED CONDITIONS. III. EVENT PROBABILITIES 21 MAR-23 MAR CLASS M 70/50/50 CLASS X 15/10/10 PROTON 15/10/10 PCAF GREEN IV. PENTICTON 10.7 CM FLUX OBSERVED 20 MAR 210 PREDICTED 21 MAR-23 MAR 215/220/225 90 DAY MEAN 20 MAR 174 V. GEOMAGNETIC A INDICES OBSERVED AFR/AP 19 MAR 006/008 ESTIMATED AFR/AP 20 MAR 005/008 PREDICTED AFR/AP 21 MAR-23 MAR 010/008-010/015-010/010 VI. GEOMAGNETIC ACTIVITY PROBABILITIES 21 MAR-23 MAR A. MIDDLE LATITUDES ACTIVE 15/15/15 MINOR STORM 05/05/05 MAJOR-SEVERE STORM 01/01/01 B. HIGH LATITUDES ACTIVE 20/20/20 MINOR STORM 05/05/05 MAJOR-SEVERE STORM 01/01/01