:Product: 19990821RSGA.txt
:Issued: 1999 Aug 21 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 233 ISSUED AT 2200Z ON 21 AUG 1999
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  20/2100Z
TO 21/2100Z:  SOLAR ACTIVITY WAS HIGH. REGION 8674 (S24E66) PRODUCED
AN M9.8/1N EVENT WITH AN ACCOMPANYING TYPE II SWEEP (700 KM/S) AT
20/2310, AND A 480 SFU 10 CM BURST. REGION 8674 ALSO PRODUCED AN
M3/1B EVENT WITH AN ACCOMPANYING WEAK TYPE II (500 KM/S), AND A 290
SFU 10CM BURST AT 21/1634UT. THE ONLY OTHER REGION OF NOTE WAS
REGION 8668 (N22W11) WHICH PRODUCED A 7 DEGREE DISAPPEARING SOLAR
FILAMENT WITH AN OPTICAL SUBFLARE AT 21/1416UT.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE
MODERATE WITH AN ISOLATED CHANCE OF AN X-CLASS EVENT FROM REGION
8674.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 20/2100Z TO 21/2100Z:
THE GEOMAGNETIC FIELD WAS QUIET TO UNSETTLED. THE GREATER THAN 2 MEV
ELECTRON FLUX AT GEOSYNCHRONOUS ORBIT WAS AT HIGH LEVELS FOR THE
ENTIRE PERIOD.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO BE QUIET TO UNSETTLED.
III.  EVENT PROBABILITIES 22 AUG-24 AUG
CLASS M    60/60/60
CLASS X    10/10/10
PROTON     01/01/01
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           21 AUG 161
PREDICTED   22 AUG-24 AUG  165/170/175
90 DAY MEAN        21 AUG 163
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 20 AUG  022/033
ESTIMATED AFR/AP 21 AUG  010/010
PREDICTED AFR/AP 22 AUG-24 AUG  010/008-010/008-010/008
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 22 AUG-24 AUG
A.  MIDDLE LATITUDES
ACTIVE                15/15/15
MINOR STORM           05/05/05
MAJOR-SEVERE STORM    01/01/01
B.  HIGH LATITUDES
ACTIVE                20/20/20
MINOR STORM           10/10/10
MAJOR-SEVERE STORM    01/01/01