:Product: 19990720RSGA.txt
:Issued: 1999 Jul 20 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 201 ISSUED AT 2200Z ON 20 JUL 1999
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  19/2100Z
TO 20/2100Z:  SOLAR ACTIVITY WAS LOW, SEVERAL C-CLASS X-RAY EVENTS
WERE OBSERVED OVER THE PAST 24 HOURS.  THE LARGEST  WAS A C4/SF  AT
20/0026Z WHICH WAS OPTICALLY CORRELATED TO REGION 8636 (N20E36).
REGION 8636 EXHIBITED SOME GROWTH AND HAS A BETA GAMMA MAGNETIC
CONFIGURATION.   REGION 8640 (N17E79), AN HSX SPOT GROUP, WAS
NUMBERED TODAY.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE LOW
TO MODERATE.  REGION 8636 CONTINUES TO HAVE THE BEST POTENTIAL FOR
M-CLASS EVENTS.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 19/2100Z TO 20/2100Z:
THE GEOMAGNETIC FIELD WAS QUIET TO UNSETTLED.  SOLAR WIND VELOCITIES
INCREASED SLIGHLTY AFTER 20/1000Z BUT REMAINED BELOW 380 KM/S.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO BE QUIET TO UNSETTLED.  THE UNSETTLED CONDITIONS MAY BE
THE RESULT OF A CME EARLY ON THE 19TH.  ISOLATED ACTIVE CONDITIONS
ARE POSSIBLE ON DAY TWO, ESPECIALLY IN THE HIGHER LATITUDES.  ALSO,
SOME MINOR EFFECTS MAY OCCUR FROM A SMALL CORONAL HOLE STREAM
IMPACTING THE EARTH AS IT ENTERS THE SOLAR WESTERN HEMISPHERE.
III.  EVENT PROBABILITIES 21 JUL-23 JUL
CLASS M    50/50/50
CLASS X    05/05/05
PROTON     05/05/05
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           20 JUL 140
PREDICTED   21 JUL-23 JUL  145/150/160
90 DAY MEAN        20 JUL 153
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 19 JUL  003/004
ESTIMATED AFR/AP 20 JUL  006/007
PREDICTED AFR/AP 21 JUL-23 JUL  008/007-014/015-012/010
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 21 JUL-23 JUL
A.  MIDDLE LATITUDES
ACTIVE                20/30/20
MINOR STORM           05/05/05
MAJOR-SEVERE STORM    01/01/01
B.  HIGH LATITUDES
ACTIVE                25/35/25
MINOR STORM           10/10/10
MAJOR-SEVERE STORM    01/01/01