:Product: 19990902RSGA.txt
:Issued: 1999 Sep 02 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 245 ISSUED AT 2200Z ON 02 SEP 1999
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  01/2100Z
TO 02/2100Z:  SOLAR ACTIVITY HAS BEEN LOW FOR THE PAST 24 HOURS. MOST
OF THE 8 SPOTTED REGIONS DECLINED IN WHITE LIGHT AND MAGNETIC
COMPLEXITY.  HOWEVER ONE REGION EMERGED RAPIDLY NEAR N10W06 AND WAS
NUMBERED AS REGION 8687.  REGION 8675 (N19W41) PRODUCED A C6/2F LONG
DURATION FLARE THAT MAXED AT 1828 UT. A FILAMENT NEAR N25W05
DISAPPEARED BETWEEN 01/1923 AND  02/0720 UT. ANOTHER DARK FILAMENT
NEAR S30W15 DISAPPEARED BETWEEN 02/0720-1527 UT IN A PARTICULARLY
INTERESTING AREA OF EVOLVING LARGE-SCALE MAGNETIC FIELDS.  AN
ERUPTIVE PROMINENCE THAT COULD BE SEEN OUT TO 0.49 SOLAR RADIUS WAS
OBSERVED ON THE SOUTHEAST LIMB (S27) NEAR 1400 UT.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE LOW
FOR THE NEXT THREE DAYS. REGIONS 8681 (N21W56) AND 8675 HAVE A SMALL
PROBABILITY OF ISOLATED M-CLASS X-RAY FLARES.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 01/2100Z TO 02/2100Z:
GEOMAGNETIC CONDITIONS HAVE RANGED BETWEEN QUIET AND ACTIVE FOR THE
LAST 24 HOURS.  THE GEOMAGNETIC FIELD IS CONTINUING TO BE INFLUENCED
BY A STEADY, POSITIVE POLARITY (AWAY) SOLAR WIND STREAM OF MODERATE
SPEED (NEAR 450 KM/S). THE INTERPLANETARY MAGNETIC FIELD INTENSITY
WAS APPROXIMATELY 10 NT, AND WAS PREDOMINATELY SOUTHWARD,
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO PERSIST AT UNSETTLED TO OCCASIONALLY ACTIVE LEVELS
TOMORROW, DECREASING TOWARD GENERALLY UNSETTLED CONDITIONS BY THE
END OF THE FORECAST PERIOD. HOWEVER, DISTURBED SOLAR WIND FROM ANY
OF THE SEVERAL ERUPTIVE EVENTS OBSERVED TODAY MAY RAISE ACTIVITY TO
NEAR-STORM LEVELS ON SEPTEMBER 6 AND 7.
III.  EVENT PROBABILITIES 03 SEP-05 SEP
CLASS M    30/20/20
CLASS X    10/05/05
PROTON     05/05/05
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           02 SEP 157
PREDICTED   03 SEP-05 SEP  150/140/130
90 DAY MEAN        02 SEP 168
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 01 SEP  014/022
ESTIMATED AFR/AP 02 SEP  010/012
PREDICTED AFR/AP 03 SEP-05 SEP  015/010-010/010-010/010
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 03 SEP-05 SEP
A.  MIDDLE LATITUDES
ACTIVE                15/05/05
MINOR STORM           10/05/05
MAJOR-SEVERE STORM    05/01/01
B.  HIGH LATITUDES
ACTIVE                20/20/20
MINOR STORM           15/10/10
MAJOR-SEVERE STORM    05/05/01