NOAA/USAF Report of Solar-Geophysical Activity 5 August 2000
:Product: Report of Solar-Geophysical Activity :Issued: 2000 Aug 05 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 218 ISSUED AT 2200Z ON 05 AUG 2000 IA. ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM 04/2100Z TO 05/2100Z: SOLAR ACTIVITY WAS LOW. ONLY TWO LOW C-CLASS EVENTS OCCURRED - AN OPTICALLY UNCORRELATED C1 FLARE AT 05/0433Z AND A C1/SF AT 05/0140Z FROM DEVELOPING REGION 9110 (S19W07). MINOR GROWTH WAS ALSO OBSERVED IN REGIONS 9114 (N12E41) AND 9115 (N16E56), BOTH PRODUCING OCCASIONAL SMALL FLARES AND BRIGHTENINGS. NEW REGIONS 9117 (S09W07), 9118 (N18W02), AND 9119 (S13E08) WERE NUMBERED TODAY. IB. SOLAR ACTIVITY FORECAST: SOLAR ACTIVITY IS EXPECTED TO REMAIN LOW. OCCASIONAL LOW C-CLASS FLARES ARE EXPECTED. IIA. GEOPHYSICAL ACTIVITY SUMMARY 04/2100Z TO 05/2100Z: THE GEOMAGNETIC FIELD WAS AT QUIET TO MAJOR STORM LEVELS. A SINGLE PERIOD OF MAJOR STORMING, MOSTLY AT HIGH LATITUDES, OCCURRED BETWEEN 05/06 - 09Z. THE PERIOD BEGAN WITH QUIET TO UNSETTLED CONDITIONS, BUT BY 05/06Z, SOLAR WIND SPEED BEGAN TO INCREASE, REACHING 600KM/S BY AROUND 05/10Z. BZ SUSTAINED EXTENDED PERIODS OF NEAR -10NT. AT THIS POINT IT IS DIFFICULT TO SAY FOR CERTAIN THE ORIGIN OF THE DISTURBANCE, BUT IT MAY BE FROM HIGH-SPEED CORONAL HOLE FLOW, PRECEDED BY A SUBSTANTIAL CO-ROTATING INTERACTION REGION. IIB. GEOPHYSICAL ACTIVITY FORECAST: THE GEOMAGNETIC FIELD IS EXPECTED TO BE AT QUIET TO ACTIVE LEVELS THROUGH DAY ONE WHILE THE PRESENT DISTURBANCE SUBSIDES. ISOLATED MINOR STORM PERIODS AT HIGH LATITUDES ARE LIKELY. QUIET TO UNSETTLED CONDITIONS SHOULD PREVAIL THROUGH DAYS TWO AND THREE. III. EVENT PROBABILITIES 06 AUG-08 AUG CLASS M 25/30/30 CLASS X 01/01/05 PROTON 01/01/01 PCAF GREEN IV. PENTICTON 10.7 CM FLUX OBSERVED 05 AUG 159 PREDICTED 06 AUG-08 AUG 165/170/175 90 DAY MEAN 05 AUG 190 V. GEOMAGNETIC A INDICES OBSERVED AFR/AP 04 AUG 013/018 ESTIMATED AFR/AP 05 AUG 023/025 PREDICTED AFR/AP 06 AUG-08 AUG 015/015-010/010-010/010 VI. GEOMAGNETIC ACTIVITY PROBABILITIES 06 AUG-08 AUG A. MIDDLE LATITUDES ACTIVE 50/30/30 MINOR STORM 20/10/10 MAJOR-SEVERE STORM 10/01/01 B. HIGH LATITUDES ACTIVE 55/35/35 MINOR STORM 30/15/15 MAJOR-SEVERE STORM 15/05/01