:Product: 19980320RSGA.txt :Issued: 1998 Mar 20 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 079 ISSUED AT 2200Z ON 20 MAR 1998 IA. ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM 19/2100Z TO 20/2100Z: SOLAR ACTIVITY WAS LOW. REGION 8179 (S22W69) PRODUCED TWO C-CLASS FLARES, A C2.8/SF AT 20/1857Z AND A C1/SF AT 20/2030Z, PLUS A FEW VERY MINOR SUBFAINT FLARES. SEVEN UNCORRELATED C-CLASS X-RAY BURSTS WERE DETECTED AS WELL. THESE MAY HAVE ORIGINATED JUST BEHIND THE SE LIMB (S26) WHERE AN ACTIVE SURGE REGION WAS VISIBLE MOST OF THE DAY AND AN ERUPTIVE PROMINENCE WAS OBSERVED ENDING AT 20/1234Z. THIS IS LIKELY THE RETURN OF REGION 8171 (S24L235), BUT NO SPOTS HAVE APPEARED ON THE LIMB YET. IB. SOLAR ACTIVITY FORECAST: SOLAR ACTIVITY IS EXPECTED TO BE LOW TO MODERATE. REGION 8179, STILL GROWING SLOWLY, HAS A GOOD CHANCE OF C-CLASS ACTIVITY, A FAIR CHANCE OF ISOLATED M-CLASS ACTIVITY AND A SMALL CHANCE OF PRODUCING AN ISOLATED X-CLASS EVENT. IIA. GEOPHYSICAL ACTIVITY SUMMARY FROM 19/2100Z TO 20/2100Z: THE GEOMAGNETIC FIELD HAS BEEN QUIET TO UNSETTLED. THE GREATER THAN TWO MEV ENERGETIC ELECTRON FLUX RANGED FROM MODERATE TO HIGH. IIB. GEOPHYSICAL ACTIVITY FORECAST: THE GEOMAGNETIC FIELD IS EXPECTED TO BE QUIET TO UNSETTLED FOR THE ENTIRE FORECAST PERIOD. III. EVENT PROBABILITIES 21 MAR-23 MAR CLASS M 45/45/25 CLASS X 10/10/05 PROTON 05/05/05 PCAF GREEN IV. PENTICTON 10.7 CM FLUX OBSERVED 20 MAR 127 PREDICTED 21 MAR-23 MAR 125/118/116 90 DAY MEAN 20 MAR 098 V. GEOMAGNETIC A INDICES OBSERVED AFR/AP 19 MAR 003/004 ESTIMATED AFR/AP 20 MAR 007/008 PREDICTED AFR/AP 21 MAR-23 MAR 005/012-005/010-005/005 VI. GEOMAGNETIC ACTIVITY PROBABILITIES 21 MAR-23 MAR A. MIDDLE LATITUDES ACTIVE 10/10/10 MINOR STORM 05/05/05 MAJOR-SEVERE STORM 01/01/01 B. HIGH LATITUDES ACTIVE 15/15/10 MINOR STORM 10/10/05 MAJOR-SEVERE STORM 05/05/01