:Product: 19990314RSGA.txt
:Issued: 1999 Mar 14 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 073 ISSUED AT 2200Z ON 14 MAR 1999
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  13/2100Z
TO 14/2100Z:  SOLAR ACTIVITY REMAINED AT MODERATE LEVELS. REGION 8487
(N17E25) DISPLAYED NO REMARKABLE CHANGES IN SIZE OR COMPLEXITY, BUT
PRODUCED TWO LOW-LEVEL M-CLASS FLARES: AN M2/1N AT 14/0127Z AND AN
M1/SF AT 14 /1010Z. MINOR DISCRETE RADIO BURSTS ACCOMPANIED BOTH
FLARES. REGION 8485 (N23W09) REMAINED A MODERATELY-LARGE SUNSPOT
GROUP WITH MIXED POLARITIES. IT SHOWED AN OVERALL INCREASE IN
ACTIVITY AFTER 14/0000Z AND PRODUCED A FEW C-CLASS SUBFLARES, NONE
OF WHICH HAD SIGNIFICANT RADIO EMISSION. NEW REGION 8488 (S27E40)
WAS NUMBERED TODAY.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE LOW
TO MODERATE. REGIONS 8485 AND 8487 MAY PRODUCE ISOLATED M-CLASS
FLARES SOMETIME DURING THE PERIOD.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 13/2100Z TO 14/2100Z:
GEOMAGNETIC FIELD ACTIVITY INCREASED FROM QUIET TO QUIET TO ACTIVE
LEVELS BEGINNING AROUND 14/0900Z IN RESPONSE TO SIGNIFICANT CHANGES
IN THE SOLAR WIND FLOW (AS MEASURED BY THE ACE SPACECRAFT). CHANGES
INCLUDED A VELOCITY INCREASE FROM 380 - 640 KM/SEC AND INCREASED IMF
BZ VARIABILITY WITH MAXIMUM SOUTHERLY DEFLECTIONS TO MINUS 10 NT
(GSM).
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO VARY FROM QUIET TO ACTIVE LEVELS DURING THE FIRST TWO
DAYS DECREASING TO QUIET TO UNSETTLED LEVELS ON THE FINAL DAY. THE
GT 2 MEV ELECTRON FLUX AT GEOSYNCHRONOUS ALTITUDE MAY REACH HIGH
LEVELS SOMETIME DURING THE FORECAST PERIOD.
III.  EVENT PROBABILITIES 15 MAR-17 MAR
CLASS M    40/40/30
CLASS X    05/05/05
PROTON     05/05/05
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           14 MAR 150
PREDICTED   15 MAR-17 MAR  155/150/140
90 DAY MEAN        14 MAR 142
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 13 MAR  004/007
ESTIMATED AFR/AP 14 MAR  015/015
PREDICTED AFR/AP 15 MAR-17 MAR  015/015-015/012-012/010
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 15 MAR-17 MAR
A.  MIDDLE LATITUDES
ACTIVE                40/40/30
MINOR STORM           10/10/05
MAJOR-SEVERE STORM    01/01/01
B.  HIGH LATITUDES
ACTIVE                45/45/35
MINOR STORM           15/15/10
MAJOR-SEVERE STORM    01/01/01