:Product: 19981109RSGA.txt
:Issued: 1998 Nov 09 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 313 ISSUED AT 2200Z ON 09 NOV 1998
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  08/2100Z
TO 09/2100Z:  SOLAR ACTIVITY REMAINED MODERATE. REGION 8375 (N21W74)
PRODUCED AN M1/1F AT 08/2256Z. THIS REGION RETAINED ITS MIXED
POLARITIES AND ITS AREAL COVERAGE IN WHITE LIGHT WAS UNCHANGED. NEW
REGION 8384 (S27E78) APPEARED AS A MODERATE SIZE H CLASS SPOT. A
SUSPECTED SPRAY OCCURRED FROM THIS REGION BETWEEN 09/0134-0216Z.
THIS EVENT MAY HAVE BEEN ASSOCIATED WITH A C3 X-RAY ENHANCEMENT AT
09/0153Z. A FILAMENT LOCATED NEAR N24E25 FADED BETWEEN
08/2318-2330Z. SEVERAL CORONAL MASS EJECTIONS WERE OBSERVED IN THE
SOHO CORONAGRAPH DURING THE PERIOD. THE LARGEST WERE FROM MODERATELY
HIGH LATITUDES ON THE SOUTHEAST AND NORTHWEST LIMBS. THE MAUNA LOA
CORONAGRAPH OBSERVED AN ERUPTIVE PROMINENCE AND ASSOCIATED CORONAL
MASS EJECTION FROM NW40-70 BEGINNING AT 09/1915Z.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY SHOULD BE LOW TO
MODERATE FOR 10-11 NOV. REGION 8375 REMAINS CAPABLE OF PRODUCING
OCCASIONAL M-CLASS EVENTS AND ISOLATED LARGER EVENTS.  REGION 8384
COULD PRODUCE AN ISOLATED M-CLASS EVENT.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 08/2100Z TO 09/2100Z:
THE GEOMAGNETIC FIELD RANGED FROM UNSETTLED TO MAJOR STORM LEVELS.
THE MOST DISTURBED PERIOD WAS FROM 09/0600-1200Z. SOME HIGH LATITUDE
SITES EXPERIENCED SEVERE STORMING DURING THAT TIME. SOLAR WIND DATA
WAS CHARACTERIZED BY A STRONG SOUTHWARD BZ BEGINNING AROUND
09/0330Z, DECREASING VELOCITY, AND DECREASING TOTAL FIELD MAGNITUDE.
A FORBUSH DECREASE OF APPROXIMATELY 6 PERCENT WAS OBSERVED NEAR
09/0100Z.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD SHOULD BE
AT UNSETTLED TO MINOR STORM LEVELS FOR 10 NOV. PERIODS OF MAJOR
STORMING ARE POSSIBLE ON THAT DAY. QUIET TO ACTIVE CONDITIONS ARE
EXPECTED ON 11 NOV AS THE CURRENT DISTURBANCE SUBSIDES. QUIET TO
UNSETTLED CONDITIONS SHOULD OCCUR ON 12 NOV.
III.  EVENT PROBABILITIES 10 NOV-12 NOV
CLASS M    65/60/15
CLASS X    30/25/10
PROTON     30/25/20
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           09 NOV 162
PREDICTED   10 NOV-12 NOV  162/156/145
90 DAY MEAN        09 NOV 133
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 08 NOV  036/068
ESTIMATED AFR/AP 09 NOV  035/072
PREDICTED AFR/AP 10 NOV-12 NOV  020/025-012/012-010/012
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 10 NOV-12 NOV
A.  MIDDLE LATITUDES
ACTIVE                20/20/20
MINOR STORM           10/10/10
MAJOR-SEVERE STORM    15/10/05
B.  HIGH LATITUDES
ACTIVE                15/10/10
MINOR STORM           10/05/05
MAJOR-SEVERE STORM    15/05/05