:Product: Report of Solar-Geophysical Activity
:Issued: 2000 Feb 23 2210 UT
# 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 054 ISSUED AT 2200Z ON 23 FEB 2000
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  22/2100Z
TO 23/2100Z:  SOLAR ACTIVITY WAS MODERATE DUE TO A SINGLE
UNCORRELATED M1 X-RAY FLARE AT 22/2147Z.  THE FLARE WAS PROBABLY THE
SUPERPOSITION OF THREE EVENTS, A LONG DURATION C9 AND IMPULSIVE M1
AND C7 FLARES, BUT WITHOUT OPTICAL CORRELATION IT IS IMPOSSIBLE TO
BE SURE.  THE REMAINDER OF THE PERIOD SAW NUMEROUS UNCORRELATED
C-CLASS FLARES AMIDST A BACKGROUND X-RAY FLUX AVERAGING NEARLY C2.
THREE NEW REGIONS WERE NUMBERED TODAY, 8884 (S11W74), 8885 (N11W43),
AND 8886 (S14E31).
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE
PREDOMINANTLY LOW, WITH ISOLATED M-CLASS FLARES POSSIBLE.  SOLAR
ACTIVITY IS EXPECTED TO BE ON THE RISE BY THE END OF THE PERIOD.
IMAGERY FROM THE YOHKOH SOFT X-RAY TELESCOPE SUGGESTS AT LEAST TWO
LARGE ACTIVE REGIONS WILL SOON BE ROTATING ONTO THE DISK.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 22/2100Z TO 23/2100Z:
THE GEOMAGNETIC FIELD WAS PREDOMINANTLY QUIET TO UNSETTLED.  THE
FIELD INCREASED TO ACTIVE BETWEEN 15Z AND 18Z DUE TO THE ARRIVAL OF
A CO-ROTATING INTERACTION REGION (CIR) SEEN IN ACE DATA.  THIS CIR
BROUGHT INCREASED SOLAR WIND VELOCITIES AND MAGNETIC FIELD STRENGTH;
BZ FLUCTUATED WILDLY BETWEEN -15 AND 10 NT.  THE CIR HERALDS THE
EXPECTED RETURN OF A HIGH SPEED CORONAL HOLE STREAM.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO BE UNSETTLED TO ACTIVE IN THE MIDDLE LATITUDES AND
UNSETTLED TO MINOR STORM IN THE HIGHER LATITUDES FOR THE FIRST TWO
DAYS OF THE FORECAST PERIOD DUE TO THE EFFECTS OF A RECURRENT
CORONAL HOLE STREAM.  ON THE THIRD DAY ACTIVITY IS EXPECTED TO
DIMINISH.
III.  EVENT PROBABILITIES 24 FEB-26 FEB
CLASS M    30/30/30
CLASS X    05/05/05
PROTON     01/01/01
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           23 FEB 185
PREDICTED   24 FEB-26 FEB  185/185/190
90 DAY MEAN        23 FEB 164
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 22 FEB  005/005
ESTIMATED AFR/AP 23 FEB  010/012
PREDICTED AFR/AP 24 FEB-26 FEB  020/023-020/018-015/015
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 24 FEB-26 FEB
A.  MIDDLE LATITUDES
ACTIVE                50/50/35
MINOR STORM           15/15/05
MAJOR-SEVERE STORM    01/01/01
B.  HIGH LATITUDES
ACTIVE                60/60/45
MINOR STORM           20/20/10
MAJOR-SEVERE STORM    05/05/01