:Product: 20000411RSGA.txt
:Issued: 2000 Apr 11 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 102 ISSUED AT 2200Z ON 11 APR 2000
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  10/2100Z
TO 11/2100Z:  SOLAR ACTIVITY WAS MODERATE. REGION 8948 (S15W12) PRODUCED
TODAY'S ONLY M-CLASS EVENT, AN M1/1N AT 1810Z. THE REGION PRODUCED
ADDITIONAL SUBFLARES AND CONTINUES TO BE THE DOMINATE REGION ON THE
DISK. THERE HAS BEEN A SLOW DECLINE AND SIMPLIFICATION IN THE REGION
AND THE DELTA CONFIGURATION OF THE LAST FEW DAYS APPEARS TO BE GONE.
NEW REGION 8958 (N17E66) ROTATED IN TO VIEW TODAY AS A SIMPLE B-TYPE
REGION.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE LOW
TO MODERATE. THERE IS A FAIR-TO-GOOD CHANCE FOR CONTINUED M-CLASS
FLARES FROM REGION 8948. HOWEVER, THE RECENT DECLINING TREND IN THE
REGION WILL LIKELY LEAD TO A GRADUAL REDUCTION IN INTENSITY AND
FREQUENCY OF FLARES FROM THIS REGION.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 10/2100Z TO 11/2100Z:
THE GEOMAGNETIC FIELD WAS MOSTLY QUIET TO UNSETTLED FOR THE PAST 24
HOURS. THE GREATER THAN 2 MEV ELECTRON FLUXES ATTAINED HIGH LEVELS.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO BECOME ACTIVE SOMETIME OVER THE NEXT 24-48 HOURS. A MORE
DETAILED ANALYSIS OF YESTERDAY'S CORONAGRAPH DATA SHOWED THAT IN
FACT A VERY FAINT HALO CORONAL MASS EJECTION COULD BE ASSOCIATED
WITH THE M3 FLARE OF 9 APRIL FROM 8948. WHILE FAR FROM A CERTAINTY,
THERE IS A FAIR CHANCE FOR THE CME TO PASS BY EARTH AND ENHANCE
ACTIVITY LEVELS SOMETIME DURING THE NEXT 1-2 DAYS. CONDITIONS ARE
EXPECTED TO RETURN TO QUIET TO UNSETTLED BY THE THIRD DAY.
III.  EVENT PROBABILITIES 12 APR-14 APR
CLASS M    50/45/40
CLASS X    05/05/05
PROTON     05/05/05
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           11 APR 182
PREDICTED   12 APR-14 APR  185/190/190
90 DAY MEAN        11 APR 186
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 10 APR  014/020
ESTIMATED AFR/AP 11 APR  010/012
PREDICTED AFR/AP 12 APR-14 APR  020/020-020/015-010/007
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 12 APR-14 APR
A.  MIDDLE LATITUDES
ACTIVE                35/35/25
MINOR STORM           20/20/10
MAJOR-SEVERE STORM    15/15/05
B.  HIGH LATITUDES
ACTIVE                30/30/25
MINOR STORM           25/25/15
MAJOR-SEVERE STORM    20/20/05