:Product: 19980830RSGA.txt
:Issued: 1998 Aug 30 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 242 ISSUED AT 2200Z ON 30 AUG 1998
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  29/2100Z
TO 30/2100Z:  SOLAR ACTIVITY WAS MODERATE. THE MAJORITY OF TODAY'S
ACTIVITY CAME FROM REGION 8319 (N18W41) WHICH PRODUCED  TWO M-CLASS
FLARES: AN M1/1N AT 0541Z AND AN M1/1N AT 0937Z. THE REGION GREW
RAPIDLY OVER THE LAST 24 HOURS, MORE THAN DOUBLING IN SIZE, AND
PRODUCED VERY FREQUENT SUBFLARE ACTIVITY. THE SUNSPOT DISTRIBUTION
APPEARS TO BE TRANSITIONING FROM AN INTERMEDIATE TO COMPACT
CONFIGURATION. A THIRD M-CLASS EVENT (M1/SN WITH AN ASSOCIATED TYPE
II SWEEP) WAS PRODUCED BY 8307 (N30W65) AT 1805Z. ALL THREE OF
TODAY'S M-CLASS FLARES WERE SHORT-LIVED, IMPULSIVE EVENTS. REGION
8323 (S21E54) HAS ROTATED INTO VIEW AS A LARGE (700-800 MILLIONTHS),
COMPACT SUNSPOT GROUP. MAGNETIC OBSERVATIONS INDICATE A MIXING OF
MAGNETIC POLARITY INCLUDING A PROBABLE DELTA CONFIGURATION IN THE
REGION.THE GROUP PRODUCED A NUMBER OF SUBFLARE EVENTS DURING THE
PAST 24 HOURS.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE
MOSTLY MODERATE, BUT THERE IS A FAIR CHANCE FOR A MAJOR FLARE EVENT
OVER THE NEXT THREE DAYS FROM ANY ONE OF REGIONS 8307, 8319, AND
8323.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 29/2100Z TO 30/2100Z:
THE GEOMAGNETIC FIELD HAS BEEN UNSETTLED TO ACTIVE. HIGH SPEED
(500-580 KM/S), LOW DENSITY (1-3 P/CC) SOLAR WIND PERSISTED OVER THE
LAST 24 HOURS, AND WAS ACCOMPANIED BY A FLUCTUATING, BUT MOSTLY
NEGATIVE BZ INTERPLANETARY MAGNETIC FIELD COMPONENT (RANGING FROM +2
TO -5 NT). THE GREATER THEN 2 MEV ELECTRON FLUXES CONTINUE TO BE
HIGH.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO BE MOSTLY UNSETTLED WITH OCCASIONAL ACTIVE PERIODS FOR
THE NEXT THREE DAYS.
III.  EVENT PROBABILITIES 31 AUG-02 SEP
CLASS M    85/85/85
CLASS X    25/25/25
PROTON     35/35/35
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           30 AUG 163
PREDICTED   31 AUG-02 SEP  170/170/165
90 DAY MEAN        30 AUG 119
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 29 AUG  011/018
ESTIMATED AFR/AP 30 AUG  015/015
PREDICTED AFR/AP 31 AUG-02 SEP  015/015-015/015-010/015
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 31 AUG-02 SEP
A.  MIDDLE LATITUDES
ACTIVE                35/30/20
MINOR STORM           05/05/05
MAJOR-SEVERE STORM    01/01/01
B.  HIGH LATITUDES
ACTIVE                45/30/25
MINOR STORM           25/20/15
MAJOR-SEVERE STORM    05/05/05