:Product: 20000412RSGA.txt
:Issued: 2000 Apr 12 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 103 ISSUED AT 2200Z ON 12 APR 2000
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  11/2100Z
TO 12/2100Z:  SOLAR ACTIVITY REMAINED AT MODERATE LEVELS. REGION 8948
(S16W37) APPEARED TO STABILIZE AS A MODERATE-SIZED, MIXED-POLARITY
REGION FOLLOWING TWO DAYS OF GRADUAL DECAY. IT PRODUCED TWO M-CLASS
FLARES DURING THE PERIOD: AN M1/1N AT 11/2337Z AND AN M1/SF AT
12/0335Z. REGION 8948 ALSO PRODUCED A C2/SN FLARE AT 12/0630Z WITH
AN ASSOCIATED TYPE II RADIO SWEEP. NEW REGION 8959 (S19E29) EMERGED
JUST SOUTH OF REGION 8953 (S16E31).
IB.  SOLAR ACTIVITY FORECAST:  ACTIVITY IS EXPECTED TO BE AT LOW TO
MODERATE LEVELS. THERE IS A FAIR TO GOOD CHANCE FOR ISOLATED M-CLASS
FLARES FROM REGION 8948.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 11/2100Z TO 12/2100Z:
GEOMAGNETIC FIELD ACTIVITY WAS AT QUIET TO UNSETTLED LEVELS. THE
GREATER THAN 2 MEV ELECTRON FLUX AT GEOSYNCHRNOUS ORBIT WAS AT
MODERATE TO HIGH LEVELS.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  GEOMAGNETIC FIELD ACTIVITY IS
EXPECTED TO REMAIN AT QUIET TO UNSETTLED LEVELS. AT THIS POINT, IT
APPEARS UNLIKELY THAT WE WILL SEE ANY SIGNIFICANT EFFECTS FROM THE
FAINT HALO-CME OBSERVED EARLY ON 10 APRIL. THE GREATER THAN 2 MEV
ELECTRON FLUX AT GEOSYNCHRONOUS ORBIT IS EXPECTED TO DECLINE TO
NORMAL TO MODERATE LEVELS EARLY IN THE PERIOD.
III.  EVENT PROBABILITIES 13 APR-15 APR
CLASS M    50/45/40
CLASS X    05/05/05
PROTON     05/05/05
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           12 APR 173
PREDICTED   13 APR-15 APR  175/175/170
90 DAY MEAN        12 APR 185
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 11 APR  008/010
ESTIMATED AFR/AP 12 APR  008/005
PREDICTED AFR/AP 13 APR-15 APR  012/012-010/010-012/012
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 13 APR-15 APR
A.  MIDDLE LATITUDES
ACTIVE                20/15/20
MINOR STORM           10/05/10
MAJOR-SEVERE STORM    05/01/05
B.  HIGH LATITUDES
ACTIVE                25/20/25
MINOR STORM           15/10/15
MAJOR-SEVERE STORM    15/10/15