:Product: 20000205RSGA.txt
:Issued: 2000 Feb 05 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
::::::::::CORRECTED COPY::::::::::
SDF NUMBER 036 ISSUED AT 2200Z ON 05 FEB 2000
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  04/2100Z
TO 05/2100Z:  SOLAR ACTIVITY BECAME HIGH. REGION 8858 (N25E53)
PRODUCED AN X1/3B MAJOR FLARE AT 05/1928Z. THIS FLARE HAD AN
ASSOCIATED TYPE II RADIO SWEEP WITH 500 KM/S SHOCK SPEED AND
MODERATE CENTIMETRIC BURSTS, INCLUDING A 350 SFU 10CM BURST. A
CORONAL MASS EJECTION WAS OBSERVED TO FOLLOW THESE EVENTS. THIS
REGION WAS PRODUCING FREQUENT C-CLASS X-RAY ACTIVITY PRIOR TO THE
MAJOR FLARE, THE LARGEST WAS A C7/SF AT 05/0830Z. THOUGH RELATIVELY
SMALL AT APPROXIMATELY 200 MILLIONTHS OF WHITE LIGHT AREA, THIS
REGION IS MAGNETICALLY COMPLEX WITH STRONG GRADIENTS AND IS STILL
DEVELOPING. NOT MUCH CHANGE OBSERVED IN REGION 8851'S (N25W35) SIZE
OR COMPLEXITY, BUT FREQUENT PLAGE FLUCTUATIONS AND OCCASIONAL SMALL
C-CLASS FLARES WERE NOTED. NEW REGION 8861 (N08W15) WAS NUMBERED
TODAY.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE
MODERATE. CONTINUED C-CLASS ACTIVITY IS LIKELY WITH AN ISOLATED M OR
SMALL X-CLASS EVENT POSSIBLE FROM REGION 8858. ANOTHER MAJOR FLARE
IS POSSIBLE IN THE NEXT 48 HOURS FROM THIS REGION IF FURTHER
DEVELOPMENT OCCURS. OCCASIONAL C-CLASS FLARES ARE ALSO LIKELY FROM
REGION 8851.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 04/2100Z TO 05/2100Z:
THE GEOMAGNETIC FIELD WAS QUIET TO ACTIVE WITH MINOR STORMING
OBSERVED AT HIGH LATITUDES LATE IN THE PERIOD. QUIET CONDITIONS
PREVAILED BEFORE 05/1449Z WHEN A SMALL BUT DISTINCT SHOCK WAS
OBSERVED AT L1, MARKING THE ONSET OF THE DISTURBANCE. THE GREATER
THAN 2 MEV ELECTRON FLUX AT GEOPSYNCHRONONOUS ORBIT WAS AT MODERATE
TO HIGH LEVELS.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO BE AT UNSETTLED TO ACTIVE LEVELS AS WE FALL UNDER THE
EFFECTS OF A HIGH SPEED CORONAL HOLE STREAM.  PERIODS OF MINOR
STORMING ARE LIKELY AT HIGH LATITUDES. EXPECT THE FIELD TO RETURN TO
MOSTLY UNSETTLED CONDITIONS BY DAY THREE.
III.  EVENT PROBABILITIES 06 FEB-08 FEB
CLASS M    50/50/40
CLASS X    20/20/15
PROTON     05/05/05
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           05 FEB 168
PREDICTED   06 FEB-08 FEB  175/180/190
90 DAY MEAN        05 FEB 174
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 04 FEB  004/004
ESTIMATED AFR/AP 05 FEB  010/010
PREDICTED AFR/AP 06 FEB-08 FEB  015/015-012/015-010/009
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 06 FEB-08 FEB
A.  MIDDLE LATITUDES
ACTIVE                25/25/15
MINOR STORM           10/10/05
MAJOR-SEVERE STORM    01/01/01
B.  HIGH LATITUDES
ACTIVE                30/30/20
MINOR STORM           15/15/10
MAJOR-SEVERE STORM    01/01/01