Report of Solar-Geophysical Activity 10 September 2000
:Product: Report of Solar-Geophysical Activity :Issued: 2000 Sep 10 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 254 ISSUED AT 2200Z ON 10 SEP 2000 IA. ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM 09/2100Z TO 10/2100Z: SOLAR ACTIVITY HAS BEEN LOW. THE LARGEST EVENT OF THE DAY WAS A C1/SF FLARE AT 10/0010 UTC, FROM REGION 9158 (N29E32). X-RAY FLUX SINCE THEN HAS REMAINED AT BACKGROUND LEVELS, EXHIBITING ONLY B-CLASS FLARING. IB. SOLAR ACTIVITY FORECAST: SOLAR ACTIVITY IS EXPECTED TO BE LOW. REGIONS 9158 AND 9154 (S17W75) ARE MOST LIKELY SOURCES FOR C-CLASS FLARES. ISOLATED CHANCES FOR M-CLASS ACTIVITY STILL EXIST FROM REGIONS 9154 AND 9151 (N10W87) UNTIL THEY TRANSIT THE WEST LIMB. IIA. GEOPHYSICAL ACTIVITY SUMMARY 09/2100Z TO 10/2100Z: THE GEOMAGNETIC FIELD HAS BEEN AT QUIET LEVELS THROUGHOUT THE PERIOD. IIB. GEOPHYSICAL ACTIVITY FORECAST: THE GEOMAGNETIC FIELD IS EXPECTED TO REMAIN AT QUIET TO UNSETTLED LEVELS, WITH AN INCREASING CHANCE OF ACTIVE LEVELS NEAR THE END OF DAY ONE, DUE TO ANTICIPATED SHOCK ARRIVAL FROM THE CME ACTIVITY NOTED ON 09/0849 UTC. ACTIVE LEVELS ARE EXPECTED FOR DAY TWO AND INTO DAY THREE. A CHANCE FOR ISOLATED PERIODS OF MINOR STORMING DURING SHOCK PASSAGE ALSO EXISTS. III. EVENT PROBABILITIES 11 SEP-13 SEP CLASS M 25/20/20 CLASS X 01/01/01 PROTON 01/01/01 PCAF GREEN IV. PENTICTON 10.7 CM FLUX OBSERVED 10 SEP 141 PREDICTED 11 SEP-13 SEP 140/135/130 90 DAY MEAN 10 SEP 180 V. GEOMAGNETIC A INDICES OBSERVED AFR/AP 09 SEP 006/007 ESTIMATED AFR/AP 10 SEP 004/007 PREDICTED AFR/AP 11 SEP-13 SEP 018/020-020/020-012/012 VI. GEOMAGNETIC ACTIVITY PROBABILITIES 11 SEP-13 SEP A. MIDDLE LATITUDES ACTIVE 35/40/30 MINOR STORM 15/20/15 MAJOR-SEVERE STORM 05/05/05 B. HIGH LATITUDES ACTIVE 35/40/35 MINOR STORM 20/20/15 MAJOR-SEVERE STORM 05/05/05
