:Product: 20000226RSGA.txt
:Issued: 2000 Feb 26 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 057 ISSUED AT 2200Z ON 26 FEB 2000
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  25/2100Z
TO 26/2100Z:  SOLAR ACTIVITY REMAINED AT A LOW LEVEL. SEVERAL LOW
LEVEL C-CLASS EVENTS OCCURRED. REGION 8891 (S15E60) IS A LARGE
REGION OF OVER 700 MILLIONTHS AREA BUT EXHIBITS A BIPOLAR MAGNETIC
STRUCTURE. REGION 8882 (S16E08) SHOWED SOME MINOR MIXING OF
POLARITIES AND A WEAK DELTA CONFIGURATION MAY EXIST HERE. REGION
8889 (N20E46) IS A MODERATE SIZE E CLASS GROUP WITH A LARGE TRAILING
FILAMENT THAT WAS QUITE ACTIVE AT TIMES DURING THE PERIOD. A LONG
DURATION C2 X-RAY FLARE OCCURRED BETWEEN 26/1036-1222Z. SOHO DATA
INDICATE THIS EVENT ORIGINATED FROM BEHIND THE SOUTHWEST LIMB.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY SHOULD BE LOW TO
MODERATE. M-CLASS EVENTS ARE POSSIBLE FROM REGIONS 8882, 8889, AND
8891. THERE IS ALSO THE POSSIBILITY OF A LONG DURATION C OR M-CLASS
EVENT FROM REGION 8889 SHOULD THE NEARBY FILAMENT ERUPT. THERE IS A
SLIGHT CHANCE OF AN X-CLASS EVENT DURING THE PERIOD. THIS CHANCE
WOULD BECOME GREATER SHOULD REGIONS 8882 AND 8891 BEGIN TO EVOLVE
QUICKLY AND DEVELOP GREATER MAGNETIC COMPLEXITY.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 25/2100Z TO 26/2100Z:
THE GEOMAGNETIC FIELD RANGED FROM QUIET TO ACTIVE LEVELS. SOLAR WIND
VELOCITY CONTINUED TO SLOWLY DECLINE BUT ENDED THE PERIOD STILL
ELEVATED NEAR 600 KM/S. ENERGETIC ELECTRON FLUXES AT GEOSYNCHRONOUS
ORBIT REACHED HIGH LEVELS FOR THE SECOND CONSECUTIVE DAY.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD SHOULD BE
PREDOMINANTLY QUIET TO UNSETTLED FOR 27 FEB. ISOLATED ACTIVE PERIODS
ARE POSSIBLE AS THIS CORONAL HOLE RELATED DISTURBANCE SUBSIDES.
MOSTLY QUIET CONDITIONS ARE EXPECTED ON 28-29 FEB. ENERGETIC
ELECTRON FLUXES SHOULD REMAIN ELEVATED FOR THE NEXT FEW DAYS.
III.  EVENT PROBABILITIES 27 FEB-29 FEB
CLASS M    60/60/60
CLASS X    15/15/15
PROTON     05/05/05
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           26 FEB 215
PREDICTED   27 FEB-29 FEB  217/219/220
90 DAY MEAN        26 FEB 165
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 25 FEB  014/018
ESTIMATED AFR/AP 26 FEB  012/011
PREDICTED AFR/AP 27 FEB-29 FEB  012/008-008/010-008/010
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 27 FEB-29 FEB
A.  MIDDLE LATITUDES
ACTIVE                35/25/15
MINOR STORM           10/10/05
MAJOR-SEVERE STORM    05/01/01
B.  HIGH LATITUDES
ACTIVE                40/25/15
MINOR STORM           10/10/05
MAJOR-SEVERE STORM    05/01/01