:Product: 19990316RSGA.txt
:Issued: 1999 Mar 16 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 075 ISSUED AT 2200Z ON 16 MAR 1999
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  15/2100Z
TO 16/2100Z:  SOLAR ACTIVITY CONTINUED AT MODERATE LEVELS. REGION
8485 (N23W39) REMAINED A LARGE F-TYPE GROUP WITH MIXED POLARITIES
AND SHOWED AN OVERALL INCREASE IN ACTIVITY, THOUGH NO SIGNIFICANT
CHANGES WERE APPARENT IN ITS SIZE OR STRUCTURE. IT PRODUCED AN
IMPULSIVE M1/1F AT 16/0635UT ALONG WITH SEVERAL C-CLASS SUBFLARES.
ALL OF THESE FLARES WERE WEAK IN RADIO EMISSION. REGION 8487
(N16W02) PRODUCED ISOLATED B-CLASS SUBFLARES AND SHOWED NO
SIGNIFICANT CHANGES. A 16-DEGREE FILAMENT, LAST SEEN NEAR S35W32,
DISAPPEARED EARLY IN THE PERIOD. THERE WAS A CME ASSOCIATED WITH THE
DISAPPEARANCE, BUT IT DID NOT APPEAR TO BE EARTH-DIRECTED. NEW
REGION 8489 (N13W28) WAS NUMBERED.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE
MODERATE. REGIONS 8485 AND 8487 APPEAR CAPABLE OF PRODUCING M-CLASS
FLARES. THERE IS ALSO A SLIGHT CHANCE FOR A MAJOR FLARE FROM REGION
8485.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 15/2100Z TO 16/2100Z:
THE GEOMAGNETIC FIELD WAS QUIET.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO BE AT MOSTLY QUIET TO UNSETTLED LEVELS. HOWEVER, ACTIVE
PERIODS ARE POSSIBLE DURING THE FIRST TWO DAYS IN RESPONSE TO RECENT
CME OCCURRENCES.
III.  EVENT PROBABILITIES 17 MAR-19 MAR
CLASS M    50/45/40
CLASS X    05/05/05
PROTON     05/05/05
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           16 MAR 156
PREDICTED   17 MAR-19 MAR  155/150/145
90 DAY MEAN        16 MAR 142
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 15 MAR  011/016
ESTIMATED AFR/AP 16 MAR  005/005
PREDICTED AFR/AP 17 MAR-19 MAR  012/010-015/012-010/008
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 17 MAR-19 MAR
A.  MIDDLE LATITUDES
ACTIVE                25/30/25
MINOR STORM           05/05/05
MAJOR-SEVERE STORM    01/01/01
B.  HIGH LATITUDES
ACTIVE                30/35/30
MINOR STORM           10/10/05
MAJOR-SEVERE STORM    01/01/01