:Product: 19990721RSGA.txt
:Issued: 1999 Jul 21 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 202 ISSUED AT 2200Z ON 21 JUL 1999
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  20/2100Z
TO 21/2100Z:  SOLAR ACTIVITY WAS LOW.  SEVERAL MINOR C-CLASS X-RAY
EVENTS WERE OBSERVED OVER THE PAST 24 HOURS.  REGION 8639 (N38W38)
EXHIBITED SIGNIFICANT GROWTH, AND IS NOW A CLASS D SUNSPOT GROUP
WITH APPROXIMATELY 15 SPOTS.  REGION 8636 (N21E25) EXHIBITED SLIGHT
GROWTH DURING THE PERIOD AND HAS MAINTAINED A BETA GAMMA MAGNETIC
CONFIGURATION WITH 35 SPOTS .  REGION 8641 (N30W73), AND REGION 8642
(S18E66) WERE NUMBERED TODAY.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE LOW
TO MODERATE.  REGION 8636 REMAINS CAPABLE OF PRODUCING C-CLASS AND
ISOLATED M-CLASS EVENTS.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 20/2100Z TO 21/2100Z:
THE GEOMAGNETIC FIELD WAS QUIET TO ACTIVE.  ACTIVE CONDITIONS WERE
OBSERVED DURING THE 21/1500-1800Z PERIOD.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO BE PREDOMINATELY QUIET TO UNSETTLED WITH PERIODS OF
ACTIVE CONDITIONS DURING THE FIRST DAY OF THE PERIOD.  THE UNSETTLED
TO ISOLATED ACTIVE CONDITIONS MAY BE THE RESULT OF A CME EARLY ON
THE 19TH.  EXPECT QUIET TO UNSETTLED CONDITIONS DURING DAY TWO AND
THREE.
III.  EVENT PROBABILITIES 22 JUL-24 JUL
CLASS M    50/50/50
CLASS X    05/05/05
PROTON     01/01/01
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           21 JUL 147
PREDICTED   22 JUL-24 JUL  155/165/170
90 DAY MEAN        21 JUL 154
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 20 JUL  005/006
ESTIMATED AFR/AP 21 JUL  012/016
PREDICTED AFR/AP 22 JUL-24 JUL  014/015-010/010-008/007
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 22 JUL-24 JUL
A.  MIDDLE LATITUDES
ACTIVE                30/20/20
MINOR STORM           05/05/05
MAJOR-SEVERE STORM    01/01/01
B.  HIGH LATITUDES
ACTIVE                40/25/25
MINOR STORM           15/10/10
MAJOR-SEVERE STORM    01/01/01