:Product: 19991104RSGA.txt :Issued: 1999 Nov 04 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 308 ISSUED AT 2200Z ON 04 NOV 1999 IA. ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM 03/2100Z TO 04/2100Z: SOLAR ACTIVITY REMAINED AT LOW LEVELS. REGION 8749 (S18W39) PRODUCED SEVERAL C-CLASS FLARES EARLY IN THE PERIOD, THE LARGEST OF WHICH WAS A C8/1F AT 03/2249Z. THIS REGION SHOWED NO SIGNIFICANT CHANGES DURING THE PERIOD AND RETAINED A MIXED-POLARITY STRUCTURE. REGION 8747 (N11W38) DISPLAYED MINOR MIXED POLARITIES, BUT WAS STABLE. A BROAD BAND OF INTENSE CA XV EMISSION WAS VISIBLE ON THE NORTHEAST LIMB. IT LIKELY HERALDS THE RETURN OF A BAND OF PREVIOUSLY ACTIVE LONGITUDES (ROUGHLY L = 320 TO 280). NEW REGION 8754 (S09E66) WAS NUMBERED. IB. SOLAR ACTIVITY FORECAST: SOLAR ACTIVITY IS EXPECTED TO REMAIN MOSTLY LOW. HOWEVER, A GRADUAL INCREASING TREND IS EXPECTED DUE TO THE RETURN OF PREVIOUSLY ACTIVE LONGITUDES. IIA. GEOPHYSICAL ACTIVITY SUMMARY FROM 03/2100Z TO 04/2100Z: THE GEOMAGNETIC FIELD WAS AT MOSTLY QUIET LEVELS. IIB. GEOPHYSICAL ACTIVITY FORECAST: THE GEOMAGNETIC FIELD IS EXPECTED TO BE QUIET TO UNSETTLED EARLY IN THE PERIOD. ACTIVITY IS EXPECTED TO INCREASE TO UNSETTLED TO ACTIVE LEVELS LATE IN THE PERIOD DUE TO RECURRENT CORONAL HOLE EFFECTS. III. EVENT PROBABILITIES 05 NOV-07 NOV CLASS M 10/10/15 CLASS X 01/01/01 PROTON 01/01/01 PCAF GREEN IV. PENTICTON 10.7 CM FLUX OBSERVED 04 NOV 148 PREDICTED 05 NOV-07 NOV 150/155/165 90 DAY MEAN 04 NOV 154 V. GEOMAGNETIC A INDICES OBSERVED AFR/AP 03 NOV 004/005 ESTIMATED AFR/AP 04 NOV 006/007 PREDICTED AFR/AP 05 NOV-07 NOV 005/007-010/007-015/015 VI. GEOMAGNETIC ACTIVITY PROBABILITIES 05 NOV-07 NOV A. MIDDLE LATITUDES ACTIVE 15/20/25 MINOR STORM 05/10/15 MAJOR-SEVERE STORM 01/01/05 B. HIGH LATITUDES ACTIVE 20/25/35 MINOR STORM 10/15/20 MAJOR-SEVERE STORM 01/01/10