:Product: 19991023RSGA.txt
:Issued: 1999 Oct 23 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 296 ISSUED AT 2200Z ON 23 OCT 1999
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  22/2100Z
TO 23/2100Z:  SOLAR ACTIVITY WAS LOW. THE X-RAY BACKGROUND HAS
REMAINED ABOVE C-LEVEL. A VARIETY OF ACTIVE REGIONS PRODUCED SMALL
FLARES, INCLUDING REGION 8731 (N12W92), 8739 (S13E30), AND 8741
(S26E50). REGION 8741 WAS THE MOST ACTIVE AND HAS UNDERGONE
CONSIDERABLE GROWTH SINCE YESTERDAY. REGION 8739 HAS ALSO GROWN.
BOTH REGIONS CONTAIN MIXED POLARITIES. NEW REGION 8742 (N06E82) IS
ROTATING AROUND THE EAST LIMB.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE LOW
TO MODERATE. LOW-LEVEL M-CLASS ACTIVITY IS POSSIBLE IN REGIONS 8739
OR 8741.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 22/2100Z TO 23/2100Z:
THE GEOMAGNETIC FIELD RANGED FROM QUIET TO MINOR STORM LEVELS IN THE
WAKE OF YESTERDAY'S MAJOR STORM ACTIVITY. SOLAR WIND SPEEDS REMAINED
AT OR ABOVE 600 KM/S AND THE IMF BZ FLUCTUATED BETWEEN +/- 5 NT. THE
GREATER THAN 2 MEV ELECTRON FLUX AT GEOSYNCHRONOUS ORBIT WAS
MODERATE TO HIGH.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO BE PREDOMINATELY UNSETTLED TO ACTIVE WITH ISOLATED STORM
PERIODS AS WE RECOVER FROM THE MAJOR ACTIVITY OF OCTOBER 22. FIELD
ACTIVITY MAY ALSO BE INFLUENCED OVER THE NEXT THREE DAYS BY A
CORONAL HOLE HIGH SPEED STREAM.
III.  EVENT PROBABILITIES 24 OCT-26 OCT
CLASS M    30/30/30
CLASS X    01/01/01
PROTON     01/01/01
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           23 OCT 165
PREDICTED   24 OCT-26 OCT  165/160/155
90 DAY MEAN        23 OCT 158
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 22 OCT  045/087
ESTIMATED AFR/AP 23 OCT  020/028
PREDICTED AFR/AP 24 OCT-26 OCT  020/030-020/020-010/015
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 24 OCT-26 OCT
A.  MIDDLE LATITUDES
ACTIVE                25/25/25
MINOR STORM           15/15/15
MAJOR-SEVERE STORM    15/15/15
B.  HIGH LATITUDES
ACTIVE                25/25/25
MINOR STORM           20/20/20
MAJOR-SEVERE STORM    15/15/15