:Product: 19980318RSGA.txt
:Issued: 1998 Mar 18 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 077 ISSUED AT 2200Z ON 18 MAR 1998
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  17/2100Z
TO 18/2100Z:  SOLAR ACTIVITY WAS MODERATE BY VIRTUE OF A SINGLE,
UNCORRELATED M1 X-RAY BURST AT 18/1112Z. REGION 8179 (S21W44), NOW
AN EKC SPOT GROUP COVERING 790 MILLIONTHS OF WHITE LIGHT AREA IN A
BETA-GAMMA MAGNETIC CONFIGURATION, WAS RESPONSIBLE FOR TWO C-CLASS
FLARES, A C1.9/SF AT 18/0046Z AND A C1.2/SF AT 18/0300Z. THE
REMAINDER OF THE SPOTTED REGIONS AND THE SOLAR LIMB WERE QUIET AND
RELATIVELY STABLE. NEW REGIONS 8182 (S22W58), A BXO SPOT GROUP, AND
8183 (N22W58), A GROWING CRO SPOT GROUP, WERE NUMBERED TODAY.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO REMAIN
LOW TO MODERATE OVER THE COURSE OF THE FORECAST PERIOD. REGION 8179
HAS AN EXCELLENT CHANCE OF CONTINUED C-CLASS ACTIVITY, A GOOD CHANCE
OF ISOLATED M-CLASS FLARES, AND A SMALL CHANCE OF AN ISOLATED
X-CLASS EVENT AS THIS REGION BEGINS TO STRESS ITS MAGNETIC GRADIENT.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 17/2100Z TO 18/2100Z:
THE GEOMAGNETIC FIELD HAS BEEN MOSTLY QUIET AT ALL LATITUDES. THE
GREATER THAN 2 MEV ENERGETIC ELECTRON FLUX EXCEEDED THE ALERT
THRESHOLD AGAIN TODAY.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO BE QUIET TO UNSETTLED FOR THE NEXT 36 HOURS, THEN MOSTLY
QUIET. HIGH LATITUDE STATIONS MAY SEE ISOLATED PERIODS OF UNSETTLED
TO ACTIVE LEVELS OVER THE NEXT 48 HOURS IN RESPONSE TO THE WEAK
M1/1B PARTIAL HALO/CME OBSERVED ON 15/1900Z.
III.  EVENT PROBABILITIES 19 MAR-21 MAR
CLASS M    40/40/35
CLASS X    10/10/05
PROTON     05/05/05
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           18 MAR 127
PREDICTED   19 MAR-21 MAR  128/130/128
90 DAY MEAN        18 MAR 097
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 17 MAR  006/007
ESTIMATED AFR/AP 18 MAR  005/005
PREDICTED AFR/AP 19 MAR-21 MAR  010/010-005/008-005/008
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 19 MAR-21 MAR
A.  MIDDLE LATITUDES
ACTIVE                20/10/10
MINOR STORM           05/05/05
MAJOR-SEVERE STORM    05/05/05
B.  HIGH LATITUDES
ACTIVE                20/15/10
MINOR STORM           10/10/05
MAJOR-SEVERE STORM    05/05/05