:Product: Report of Solar-Geophysical Activity :Issued: 2000 Mar 14 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 074 ISSUED AT 2200Z ON 14 MAR 2000 IA. ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM 13/2100Z TO 14/2100Z: SOLAR ACTIVITY WAS LOW. SEVERAL LOW C-CLASS X-RAY FLARES OCCURRED PRIMARILY IN REGION 8906 (S16W09). THIS REGION IS NOW A LARGE AND MAGNETICALLY COMPLEX SPOT GROUP EXCEEDING 900 MILLIONTHS OF WHITE LIGHT AREA. PARTICULARLY STRONG MAGNETIC GRADIENTS EXIST WITHIN COMPLEX DELTA CONFIGURATIONS AND SEVERAL NEW SPOTS DEVELOPED LATE IN THE PERIOD. REGION 8910 (N10E43) PRODUCED OCCASIONAL MINOR C-CLASS EVENTS. THIS REGION EXHIBITED CONSIDERABLE GROWTH SINCE YESTERDAY AND HAS DEVELOPED MINOR MAGNETIC COMPLEXITY. A 17 DEGREE FILAMENT ERUPTED FROM NEAR S34E38 AT 14/0348Z. THREE NEW REGIONS WERE NUMBERED TODAY - REGION 8911 (N11W43), 8912 (N15W02), AND 8913 (S14E66). REMAINING REGIONS WERE MOSTLY STABLE. IB. SOLAR ACTIVITY FORECAST: SOLAR ACTIVITY IS EXPECTED TO REACH MODERATE TO HIGH LEVELS. COMPLEX REGION 8906 WILL LIKELY PRODUCE OCCASIONAL M-CLASS ACTIVITY, AND HAS POTENTIAL FOR A MAJOR FLARE. REGION 8910 WILL CONTINUE PRODUCING C-CLASS X-RAY ACTIVITY WITH THE SMALL CHANCE OF AN M-CLASS EVENT. IIA. GEOPHYSICAL ACTIVITY SUMMARY FROM 13/2100Z TO 14/2100Z: THE GEOMAGNETIC FIELD WAS QUIET WITH AN ISOLATED PERIOD OF UNSETTLED CONDITIONS BETWEEN 14/09 - 14/12Z. IIB. GEOPHYSICAL ACTIVITY FORECAST: THE GEOMAGNETIC FIELD IS EXPECTED TO CONTINUE AT QUIET LEVELS. III. EVENT PROBABILITIES 15 MAR-17 MAR CLASS M 75/75/75 CLASS X 40/40/40 PROTON 20/20/20 PCAF YELLOW IV. PENTICTON 10.7 CM FLUX OBSERVED 14 MAR 183 PREDICTED 15 MAR-17 MAR 175/175/170 90 DAY MEAN 14 MAR 175 V. GEOMAGNETIC A INDICES OBSERVED AFR/AP 13 MAR 002/004 ESTIMATED AFR/AP 14 MAR 005/006 PREDICTED AFR/AP 15 MAR-17 MAR 005/008-005/008-005/008 VI. GEOMAGNETIC ACTIVITY PROBABILITIES 15 MAR-17 MAR A. MIDDLE LATITUDES ACTIVE 15/15/20 MINOR STORM 01/01/10 MAJOR-SEVERE STORM 01/01/01 B. HIGH LATITUDES ACTIVE 20/20/30 MINOR STORM 05/05/15 MAJOR-SEVERE STORM 01/01/01