NOAA/USAF Report of Solar-Geophysical Activity 27 July 2000
:Product: Report of Solar-Geophysical Activity :Issued: 2000 Jul 27 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 209 ISSUED AT 2200Z ON 27 JUL 2000 IA. ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM 26/2100Z TO 27/2100Z: SOLAR ACTIVITY HAS BEEN MODERATE. REGION 9090 (N14W76) PRODUCED AN M2/SB FLARE AT 27/0410Z WITH AN ASSOCIATED TENFLARE. AN OPTICALLY UNCORRELATED M1 FLARE OCCURRED AT 27/1711Z, LIKELY DUE TO ACTIVITY FROM REGION 9087, BEHIND THE WEST LIMB. A FULL HALO WAS EVIDENT IN SOHO/LASCO IMAGERY BEGINNING AT 1954Z. REGIONS 9090 AND 9097 (N09W41) BOTH APPEAR TO BE DECAYING IN SIZE AND COMPLEXITY. NEW REGIONS 9104 (S23E65), 9105 (N13E81), AND 9106 (S10W15) WERE NUMBERED TODAY. IB. SOLAR ACTIVITY FORECAST: SOLAR ACTIVITY IS EXPECTED TO PERSIST AT MODERATE LEVELS FOR THE NEXT THREE DAYS. IIA. GEOPHYSICAL ACTIVITY SUMMARY 26/2100Z TO 27/2100Z: THE GEOMAGNETIC FIELD HAS BEEN QUIET TO UNSETTLED, WITH ISOLATED ACTIVE PERIODS AT HIGHER LATITUDES EARLY IN THE DAY. IIB. GEOPHYSICAL ACTIVITY FORECAST: THE GEOMAGNETIC FIELD IS EXPECTED TO BECOME ACTIVE, WITH A POSSIBILITY OF MINOR STORM PERIODS AT HIGHER LATITUDES OVER THE NEXT TWO DAYS. THIS INCREASED ACTIVITY IS EXPECTED IN RESPONSE TO THE CME OBSERVED ON 25 JULY. ACTIVITY SHOULD DECREASE TO UNSETTLED LEVELS BY THE THIRD DAY. III. EVENT PROBABILITIES 28 JUL-30 JUL CLASS M 60/50/40 CLASS X 10/10/05 PROTON 10/10/05 PCAF GREEN IV. PENTICTON 10.7 CM FLUX OBSERVED 27 JUL 162 PREDICTED 28 JUL-30 JUL 160/155/155 90 DAY MEAN 27 JUL 190 V. GEOMAGNETIC A INDICES OBSERVED AFR/AP 26 JUL 016/020 ESTIMATED AFR/AP 27 JUL 007/012 PREDICTED AFR/AP 28 JUL-30 JUL 020/030-020/025-010/012 VI. GEOMAGNETIC ACTIVITY PROBABILITIES 28 JUL-30 JUL A. MIDDLE LATITUDES ACTIVE 35/35/25 MINOR STORM 20/20/10 MAJOR-SEVERE STORM 15/15/05 B. HIGH LATITUDES ACTIVE 35/35/30 MINOR STORM 25/25/20 MAJOR-SEVERE STORM 20/20/15