:Product: 19990427RSGA.txt
:Issued: 1999 Apr 27 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 117 ISSUED AT 2200Z ON 27 APR 1999
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  26/2100Z
TO 27/2100Z:  SOLAR ACTIVITY WAS LOW DUE TO A C1/SF FLARE AT
27/2026UT IN REGION 8524 (N22E10). GROWTH IN THIS REGION APPEARS TO
BE STABILIZING. REGION 8523 (N32E04) HAS ALSO GROWN SINCE YESTERDAY
BUT HAS NOT PRODUCED ANY SIGNIFICANT FLARES.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE VERY
LOW TO LOW. REGIONS 8523 AND 8524 ARE THE MOST LIKELY AREAS FOR
ISOLATED C-CLASS ACTIVITY.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 26/2100Z TO 27/2100Z:
THE GEOMAGNETIC FIELD WAS QUIET TO UNSETTLED.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO BE QUIET TO UNSETTLED.
III.  EVENT PROBABILITIES 28 APR-30 APR
CLASS M    05/05/05
CLASS X    01/01/01
PROTON     01/01/01
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           27 APR 109
PREDICTED   28 APR-30 APR  110/110/110
90 DAY MEAN        27 APR 128
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 26 APR  006/007
ESTIMATED AFR/AP 27 APR  010/010
PREDICTED AFR/AP 28 APR-30 APR  010/015-010/020-015/020
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 28 APR-30 APR
A.  MIDDLE LATITUDES
ACTIVE                10/15/15
MINOR STORM           05/10/10
MAJOR-SEVERE STORM    01/05/05
B.  HIGH LATITUDES
ACTIVE                15/15/15
MINOR STORM           10/10/10
MAJOR-SEVERE STORM    01/05/05