:Product: 19990910RSGA.txt
:Issued: 1999 Sep 10 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 253 ISSUED AT 2200Z ON 10 SEP 1999
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  09/2100Z
TO 10/2100Z:  SOLAR ACTIVITY DECREASED TO VERY LOW LEVELS. REGION
8692 (S27E36) SHOWED A SMALL INCREASE IN SPOT NUMBER AND RETAINED A
MIXED-POLARITY (BETA-GAMMA) STRUCTURE. IT PRODUCED ISOLATED B-CLASS
SUBFLARES DURING THE PERIOD. MINOR PENUMBRAL DEVELOPMENT OCCURRED
WITHIN REGION 8690 (N13E20). THE REMAINING REGIONS WERE SMALL AND
STABLE, INCLUDING NEWLY NUMBERED REGION 8695 (N19E73).
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE LOW.
REGIONS 8690 AND 8692 MAY PRODUCE ISOLATED C-CLASS FLARES.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 09/2100Z TO 10/2100Z:
THE GEOMAGNETIC FIELD WAS AT QUIET TO UNSETTLED LEVELS DURING MOST OF
THE DAY WITH BRIEF ACTIVE TO MINOR STORM PERIODS DETECTED AT HIGH
LATITUDES.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  GEOMAGNETIC FIELD ACTIVITY IS
EXPECTED TO INCREASE TO UNSETTLED TO ACTIVE LEVELS DUE TO RECURRENT
CORONAL HOLE EFFECTS.
III.  EVENT PROBABILITIES 11 SEP-13 SEP
CLASS M    30/30/30
CLASS X    01/01/01
PROTON     01/01/01
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           10 SEP 122
PREDICTED   11 SEP-13 SEP  120/120/125
90 DAY MEAN        10 SEP 165
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 09 SEP  007/008
ESTIMATED AFR/AP 10 SEP  012/017
PREDICTED AFR/AP 11 SEP-13 SEP  015/015-015/010-015/010
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 11 SEP-13 SEP
A.  MIDDLE LATITUDES
ACTIVE                35/35/35
MINOR STORM           10/10/10
MAJOR-SEVERE STORM    05/05/05
B.  HIGH LATITUDES
ACTIVE                40/40/40
MINOR STORM           15/15/15
MAJOR-SEVERE STORM    05/05/05