:Product: 19990410RSGA.txt
:Issued: 1999 Apr 10 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 100 ISSUED AT 2200Z ON 10 APR 1999
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  09/2100Z
TO 10/2100Z:  SOLAR ACTIVITY HAS BEEN LOW.  THE MOST INTERESTING
ACTIVITY HAS BEEN IN REGION 8508 (N23W14) A SMALL BUT COMPLEX BETA
GAMMA REGION WITH A CONVOLUTED NEUTRAL LINE EXTENDING THROUGH THE
REGION. IT HAS PRODUCED SEVERAL SMALL FLARES RANGING UP TO CLASS C
INTENSITY.  OTHER REGIONS ARE STABLE OR DECLINING.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO REMAIN
LOW.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 09/2100Z TO 10/2100Z:
THE GEOMAGNETIC FIELD HAS BEEN QUIET TO UNSETTLED.  ACE SOLAR WIND
DATA INDICATES EARTH MAY BE IN A HIGH SPEED STREAM.  SOLAR WIND
VELOCITY HAS INCREASED MODERATELY ALONG WITH THE TEMPERATURE WHILE
THE DENSITY HAS DECREASED OVER THE PAST 12 HOURS.  THE SOURCE IS
INDEFINITE BUT MAY BE A SMALL, POORLY-DEFINED CORONAL HOLE VISIBLE
AROUND N22W30.  ENERGETIC ELECTRON FLUXES AT GEOSYNCHRONOUS ORBIT
HAVE REMAINED AT MODERATE LEVELS.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO BE UNSETTLED TO ACTIVE THROUGH THE NEXT 24 HOURS.
III.  EVENT PROBABILITIES 11 APR-13 APR
CLASS M    25/25/25
CLASS X    05/05/05
PROTON     05/05/05
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           10 APR 136
PREDICTED   11 APR-13 APR  132/130/128
90 DAY MEAN        10 APR 135
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 09 APR  007/005
ESTIMATED AFR/AP 10 APR  014/010
PREDICTED AFR/AP 11 APR-13 APR  012/010-010/010-010/008
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 11 APR-13 APR
A.  MIDDLE LATITUDES
ACTIVE                15/14/15
MINOR STORM           07/08/06
MAJOR-SEVERE STORM    03/03/01
B.  HIGH LATITUDES
ACTIVE                13/11/13
MINOR STORM           07/07/07
MAJOR-SEVERE STORM    04/04/03