:Product: 19971221RSGA.txt
:Issued: 1997 Dec 21 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 355 ISSUED AT 2200Z ON 21 DEC 1997
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  20/2100Z
TO 21/2100Z:  SOLAR ACTIVITY WAS LOW. TWO UNCORRELATED C-CLASS EVENTS
OCCURRED DURING THE REPORTING PERIOD, THE FIRST A C7 FLARE AT
21/0354Z, AND THE SECOND A LONG DURATION C2 EVENT AT 21/1645Z. THE
MOST PROBABLE GENERATOR OF THESE FLARES IS REGION 8124 (S22E66),
A 7-SPOT 'EAO' BETA GROUP. THE ONLY OTHER ACTIVE REGION CURRENTLY ON
THE VISIBLE DISK, REGION 8123 (N18W36), HAS BEEN QUIET WHILE DECAYING
INTO A 3-SPOT 'CSO' BETA.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO REMAIN
LOW, DUE TO THE HIGH PROBABILITY FOR CONTINUED C-CLASS ACTIVITY FROM
REGION 8124.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 20/2100Z TO 21/2100Z:
THE GEOMAGNETIC FIELD HAS BEEN QUIET AT ALL LATITUDES FOR THE PAST 24
HOURS.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO BE MOSTLY QUIET, WITH THE CHANCE FOR ISOLATED PERIODS OF
UNSETTLED CONDITIONS, FOR THE NEXT THREE DAYS.
III.  EVENT PROBABILITIES 22 DEC-24 DEC
CLASS M    10/10/10
CLASS X    01/01/01
PROTON     01/01/01
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           21 DEC 092
PREDICTED   22 DEC-24 DEC  092/092/094
90 DAY MEAN        21 DEC 093
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 20 DEC  003/002
ESTIMATED AFR/AP 21 DEC  004/003
PREDICTED AFR/AP 22 DEC-24 DEC  005/005-005/005-005/005
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 22 DEC-24 DEC
A.  MIDDLE LATITUDES
ACTIVE                15/15/15
MINOR STORM           05/05/05
MAJOR-SEVERE STORM    01/01/01
B.  HIGH LATITUDES
ACTIVE                15/15/15
MINOR STORM           05/05/05
MAJOR-SEVERE STORM    01/01/01