:Product: 19970401RSGA.txt
:Issued: 1997 Apr 01 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 091 ISSUED AT 2200Z ON 01 APR 1997
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  31/2100Z
TO 01/2100Z:  SOLAR ACTIVITY WAS MODERATE. REGION 8026 (S25E07), A 13
SPOT 'CAO' GROUP, GENERATED A SINGLE M1/1B FLARE AT 01/1348, WHICH
WAS PRECEEDED BY THREE C-CLASS EVENTS. THE REGION HAD BEEN SURGING
PRIOR TO, BUT HAD STOPPED BEFORE THE ONSET OF THE M1 EVENT. AN
ASSOCIATED HIGH SPEED DARK SURGE ACCOMPANIED THE M1 FLARE. ALL FOUR
FLARES OCCURRED NEAR THE SMALL OPPOSITE POLARITY FIELD EAST OF THE
SOUTHERNMOST PENUMBRA, WHICH SUPPORTS THE MT. WILSON SOLAR
OBSERVATORY'S MAGNETIC CLASSIFICATION OF THIS REGION AS A
BETA-GAMMA-DELTA. NUMEROUS RADIO BURSTS AT VARIOUS FREQUENCIES WERE
OBSERVED BEORE AND AFTER THE FLARE ACTIVITY. IN ADDITION, TWO
FILAMENTS DISSAPPEARED OVERNIGHT FROM REGION 8026, WITH THE LARGER
OF THE TWO (7 DEGREES) HAVING BECOME HIGHLY ACTIVE PRIOR TO
DISAPPEARING.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE VERY
LOW TO LOW, WITH A CONTINUED CHANCE FOR ISOLATED M-CLASS EVENTS FOR
THE NEXT THREE DAYS.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 31/2100Z TO 01/2100Z:
THE GEOMAGNETIC FIELD WAS MOSTLY UNSETTLED FOR THE FIRST HALF OF THE
REPORTING PERIOD, WITH A SINGLE PERIOD OF ACTIVE CONDITIONS RECORDED
AT FREDRICKSBURG DURING THE INTERVAL 01/0300-0600Z, AND THEN QUIET
FOR THE SECOND HALF OF THE DAY. THE GREATER THAN 2 MEV ELECTRONS
WERE IN THE MODERATE TO HIGH RANGE.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO BE QUIET TO UNSETTLED FOR THE NEXT THREE DAYS, WITH A
CHANCE FOR ISOLATED PERIODS OF ACTIVE CONDITIONS.
III.  EVENT PROBABILITIES 02 APR-04 APR
CLASS M    20/15/10
CLASS X    01/01/01
PROTON     01/01/01
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           01 APR 076
PREDICTED   02 APR-04 APR  076/077/078
90 DAY MEAN        01 APR 074
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 31 MAR  007/005
ESTIMATED AFR/AP 01 APR  012/010
PREDICTED AFR/AP 02 APR-04 APR  010/010-010/010-010/006
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 02 APR-04 APR
A.  MIDDLE LATITUDES
ACTIVE                20/20/20
MINOR STORM           10/10/10
MAJOR-SEVERE STORM    05/05/05
B.  HIGH LATITUDES
ACTIVE                25/25/25
MINOR STORM           15/15/15
MAJOR-SEVERE STORM    05/05/05