:Product: 19990531RSGA.txt
:Issued: 1999 May 31 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 151 ISSUED AT 2200Z ON 31 MAY 1999
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  30/2100Z
TO 31/2100Z:  SOLAR ACTIVITY WAS LOW. THE LARGEST EVENT OF THE PERIOD
WAS AN OPTICALLY UNCORRELATED C8 X-RAY BURST THAT OCCURRED AT
30/2345Z. RECENT MAGNETIC MAP ANALYSIS MADE IT CLEAR THAT REGION
8557 (S30E21) AND REGION 8560 (S24E22) SHOULD BE COMBINED AS A
SINGLE BIPOLE GROUP. THEY HAVE BEEN COMBINED AS REGION 8557. THIS
REGION DID PRODUCE A C4/SF AT 31/0810Z. REGION 8552 (N18W32)
PRODUCED AN IMPULSIVE C2/SF WITH A TYPE II SWEEP AND A MINOR
MULTI-FREQUENCY RADIO BURST AT 31/0940Z. NEW REGION 8562 (S15E22)
EMERGED RAPIDLY IN THE LAST 24 HOURS AND HAS ALREADY PRODUCED LOW
C-CLASS FLARING. NEW REGION 8563 (S25E63) WAS ALSO NUMBERED TODAY.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE LOW
TO MODERATE. BOTH REGION 8557 AND 8562 WILL LIKELY PRODUCE C-CLASS
FLARING AND THEIR PROXIMITY TO EACH OTHER COULD RESULT IN AN M-CLASS
EVENT. REGION 8552 AND 8558 (N16E30) ALSO HAVE POTENTIAL FOR C-CLASS
FLARES.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 30/2100Z TO 31/2100Z:
THE GEOMAGNETIC FIELD WAS QUIET.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO BE QUIET TO UNSETTLED.
III.  EVENT PROBABILITIES 01 JUN-03 JUN
CLASS M    50/50/50
CLASS X    10/10/10
PROTON     05/05/05
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           31 MAY 165
PREDICTED   01 JUN-03 JUN  165/165/165
90 DAY MEAN        31 MAY 131
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 30 MAY  003/005
ESTIMATED AFR/AP 31 MAY  005/010
PREDICTED AFR/AP 01 JUN-03 JUN  008/010-008/010-008/008
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 01 JUN-03 JUN
A.  MIDDLE LATITUDES
ACTIVE                20/20/20
MINOR STORM           05/05/05
MAJOR-SEVERE STORM    01/01/01
B.  HIGH LATITUDES
ACTIVE                25/25/25
MINOR STORM           05/05/05
MAJOR-SEVERE STORM    01/01/01