:Product: 19991231RSGA.txt
:Issued: 1999 Dec 31 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 365 ISSUED AT 2200Z ON 31 DEC 1999
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  30/2100Z
TO 31/2100Z:  SOLAR ACTIVITY WAS LOW. THE LARGEST EVENT THIS PERIOD
WAS A C2/SF FROM NEWLY NUMBERED REGION 8815 (N10E61). THIS REGION
EMERGED AS A SMALL, COMPACT C-CLASS SPOT GROUP. REMAINING REGIONS
WERE QUIET.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO REMAIN
AT LOW LEVELS. ISOLATED LOW LEVEL C-CLASS FLARES ARE LIKELY.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 30/2100Z TO 31/2100Z:
THE GEOMAGNETIC FIELD WAS UNSETTLED TO ACTIVE.  EFFECTS FROM A
CORONAL HOLE, HIGH SPEED SOLAR WIND STREAM THAT BEGAN YESTERDAY,
CONTINUED TODAY.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD WILL
CONTINUE AT UNSETTLED TO ACTIVE LEVELS. A LARGE, GEOEFFECTIVELY
POSITIONED CORONAL HOLE WILL PROLONG THE CURRENT DISTURBANCE THROUGH
DAY THREE.
III.  EVENT PROBABILITIES 01 JAN-03 JAN
CLASS M    10/10/10
CLASS X    05/05/05
PROTON     05/05/05
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           31 DEC 130
PREDICTED   01 JAN-03 JAN  130/130/130
90 DAY MEAN        31 DEC 176
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 30 DEC  007/008
ESTIMATED AFR/AP 31 DEC  020/021
PREDICTED AFR/AP 01 JAN-03 JAN  020/025-020/025-015/018
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 01 JAN-03 JAN
A.  MIDDLE LATITUDES
ACTIVE                65/65/50
MINOR STORM           25/25/15
MAJOR-SEVERE STORM    10/10/05
B.  HIGH LATITUDES
ACTIVE                60/60/50
MINOR STORM           30/30/20
MAJOR-SEVERE STORM    10/10/05