:Product: 19980410RSGA.txt
:Issued: 1998 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 1998
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  09/2100Z
TO 10/2100Z:  SOLAR ACTIVITY WAS LOW. SMALL C-CLASS SUBFLARES
CONTINUE FROM A VARIETY OF ACTIVE REGIONS. THE LARGEST OF THESE,
WHICH WAS ASSOCIATED WITH AN OPTICAL REPORT, WAS A C1/SF AT 10/1102Z
IN REGION 8199 (S28W42). GROWTH IN REGION 8200 (S22W07) IS SLOWING
AS THE REGION MATURES INTO A SMALL D-TYPE SUNSPOT GROUP.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE LOW
TO MODERATE. C-CLASS FLARES ARE POSSIBLE FROM REGIONS 8193 (S23W38),
8194 (S17E10), 8195 (S25E18), 8198 (S28E36), 8199 (S28W42), AND 8200
(S22W07). ALL OF THESE REGIONS ARE ALSO CAPABLE OF AN ISOLATED
M-CLASS FLARE.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 09/2100Z TO 10/2100Z:
THE GEOMAGNETIC FIELD RANGED FROM QUIET TO ACTIVE. ACTIVE CONDITIONS
WERE OBSERVED AT SEVERAL STATIONS DURING THE 10/1500-1800UT PERIOD.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO BE QUIET TO UNSETTLED.
III.  EVENT PROBABILITIES 11 APR-13 APR
CLASS M    30/30/30
CLASS X    01/01/01
PROTON     01/01/01
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           10 APR 130
PREDICTED   11 APR-13 APR  128/126/126
90 DAY MEAN        10 APR 103
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 09 APR  006/009
ESTIMATED AFR/AP 10 APR  010/010
PREDICTED AFR/AP 11 APR-13 APR  010/010-010/013-010/010
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 11 APR-13 APR
A.  MIDDLE LATITUDES
ACTIVE                15/15/15
MINOR STORM           10/10/10
MAJOR-SEVERE STORM    05/05/05
B.  HIGH LATITUDES
ACTIVE                15/15/15
MINOR STORM           10/10/10
MAJOR-SEVERE STORM    05/05/05