:Product: 19981123RSGA.txt
:Issued: 1998 Nov 23 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 327 ISSUED AT 2200Z ON 23 NOV 1998
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  22/2100Z
TO 23/2100Z:  SOLAR ACTIVITY REMAINED AT HIGH LEVELS. REGION 8384
(S26W101) PRODUCED ANOTHER MAJOR FLARE AS IT CONTINUED TO ROTATE
BEYOND THE WEST LIMB. THE FLARE WAS AN X2/SF AT 23/0644UT WITH AN
ASSOCIATED SIGNIFICANT TYPE IV RADIO SWEEP, A LOOP PROMINENCE
SYSTEM, AND MODERATE DISCRETE FREQUENCY RADIO EMISSION. OPTICALLY
UNCORRELATED, LOW-LEVEL M-CLASS X-RAY FLARES WERE DETECTED AT
22/2215UT AND 23/1121UT. A SPRAY REACHING 0.3 SOLAR RADII WAS SEEN
ON THE NORTHEAST LIMB NEAR N20 AND WAS LIKELY ASSOCIATED WITH THE
RETURN OF OLD REGION 8375 (N19, L = 185). A 200 SFU TENFLARE WAS
DETECTED DURING THE SPRAY. NEW REGION 8393 (S18E71) WAS NUMBERED
TODAY AS A SMALL D-TYPE. IT IS THE RETURN OF OLD REGION 8379, WHICH
DID NOT PRODUCE SIGNIFICANT ACTIVITY DURING ITS LAST ROTATION. NO
SIGNIFICANT GROWTH OR DECAY WAS NOTED IN THE REMAINING REGIONS.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE LOW
TO MODERATE. M-CLASS FLARE PROBABILITIES MAY INCREASE UPON THE
RETURN OF OLD REGION 8375, WHICH PRODUCED A MAJOR FLARE AND A SOLAR
PROTON EVENT DURING ITS LAST ROTATION. THERE IS STILL A SMALL, BUT
DIMINISHING CHANCE FOR AN ISOLATED M-CLASS FLARE FROM BEYOND THE
SOUTHWEST LIMB.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 22/2100Z TO 23/2100Z:
THE GEOMAGNETIC FIELD WAS AT QUIET TO UNSETTLED LEVELS. THE PROTON
FLUX ENHANCEMENT AT GT 10 MEV (THAT FOLLOWED YESTERDAY'S X3/1N
FLARE) DECLINED TO BACKGROUND LEVELS.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO BE AT UNSETTLED TO ACTIVE LEVELS DURING THE FIRST TWO
DAYS, THEN DECLINE TO UNSETTLED LEVELS ON DAY THREE. THE GT 2 MEV
ELECTRON FLUX MAY RISE TO HIGH LEVELS DURING THE LATTER HALF OF THE
FORECAST PERIOD.
III.  EVENT PROBABILITIES 24 NOV-26 NOV
CLASS M    40/30/30
CLASS X    10/01/01
PROTON     10/01/01
PCAF       YELLOW
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           23 NOV 130
PREDICTED   24 NOV-26 NOV  125/125/125
90 DAY MEAN        23 NOV 131
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 22 NOV  006/007
ESTIMATED AFR/AP 23 NOV  010/009
PREDICTED AFR/AP 24 NOV-26 NOV  015/015-015/015-010/010
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 24 NOV-26 NOV
A.  MIDDLE LATITUDES
ACTIVE                30/30/20
MINOR STORM           10/10/05
MAJOR-SEVERE STORM    01/01/01
B.  HIGH LATITUDES
ACTIVE                40/40/20
MINOR STORM           10/10/05
MAJOR-SEVERE STORM    01/01/01