:Product: 19990313RSGA.txt
:Issued: 1999 Mar 13 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 072 ISSUED AT 2200Z ON 13 MAR 1999
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  12/2100Z
TO 13/2100Z:  SOLAR ACTIVITY INCREASED TO MODERATE LEVELS. REGION
8487 (N17E39) REMAINED A RELATIVELY SMALL D-TYPE GROUP AND SHOWED
MINOR PENUMBRAL GROWTH AS WELL AS SOME MAGNETIC SHEAR IN THE
VICINITY OF THE DOMINANT LEADER SPOT. IT PRODUCED AN IMPULSIVE M1/1N
AT 13/2034Z AND NUMEROUS SUBFLARES EARLIER IN THE DAY, A FEW OF
WHICH REACHED C-CLASS. NONE OF THESE FLARES WERE IMPRESSIVE IN RADIO
EMISSION. REGION 8485 (N23E00) REMAINED A MODERATE-SIZED E-TYPE
GROUP WITH SOME MIXED POLARITIES. IT WAS GENERALLY STABLE AND
PRODUCED ISOLATED SUBFARES. THE REMAINING REGIONS WERE QUIET AND
STABLE.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE AT
MOSTLY LOW LEVELS. HOWEVER, ANOTHER ISOLATED M-CLASS FLARE COULD
OCCUR FROM REGION 8487 SOMETIME DURING THE PERIOD. REGION 8485 ALSO
PROVIDES A SLIGHT CHANCE FOR AN ISOLATED M-CLASS FLARE.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 12/2100Z TO 13/2100Z:
GEOMAGNETIC FIELD ACTIVITY INCREASED TO UNSETTLED TO ACTIVE LEVELS
DURING 13/1200 - 1400Z. OTHERWISE, THE FIELD WAS AT QUIET TO
UNSETTLED LEVELS.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO BE AT UNSETTLED TO ACTIVE LEVELS THROUGH THE PERIOD.
BRIEF MINOR STORM PERIODS ARE ALSO POSSIBLE. THIS ACTIVITY IS
EXPECTED IN RESPONSE TO CME EFFECTS. AN ISOLATED, POSITIVE POLARITY
CORONAL HOLE MAY ALSO DISTURB THE FIELD SOMETIME DURING THE PERIOD.
III.  EVENT PROBABILITIES 14 MAR-16 MAR
CLASS M    30/30/30
CLASS X    05/05/05
PROTON     05/05/05
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           13 MAR 144
PREDICTED   14 MAR-16 MAR  145/145/140
90 DAY MEAN        13 MAR 142
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 12 MAR  009/010
ESTIMATED AFR/AP 13 MAR  007/009
PREDICTED AFR/AP 14 MAR-16 MAR  020/015-015/012-015/010
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 14 MAR-16 MAR
A.  MIDDLE LATITUDES
ACTIVE                45/40/40
MINOR STORM           20/10/10
MAJOR-SEVERE STORM    05/01/01
B.  HIGH LATITUDES
ACTIVE                55/45/45
MINOR STORM           25/15/15
MAJOR-SEVERE STORM    10/05/05