:Product: 19980315RSGA.txt
:Issued: 1998 Mar 15 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 074 ISSUED AT 2200Z ON 15 MAR 1998
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  14/2100Z
TO 15/2100Z:  SOLAR ACTIVITY BECAME MODERATE. REGION 8179 (S22W04)
PRODUCED AN M1/1F AT 15/1616Z. AN M1/1B FLARE ERUPTED AT 15/1911Z.
MINOR RADIO BURSTS ACCOMPANIED THIS FLARE INCLUDING AN 860 F.U.
BURST ON 410 MHZ. FREQUENT C-CLASS SUBFLARES ALSO OCCURRED
THROUGHOUT THE PERIOD. X-RAY BASELINE HAS BEEN ON A STEADY INCREASE,
EXCEEDING C-CLASS SINCE 15/1430Z. REGION 8179 CONTINUED ITS
IMPRESSIVE DEVELOPMENT AND IS NOW A 45 SPOT, E-TYPE GROUP WITH 670
MILLIONTHS OF AREAL COVERAGE. OBSERVATORIES REPORTED MAJOR GROWTH IN
PENUMBRA ON LEADER AND TRAILER SPOTS. A MAGNETIC DELTA CONFIGURATION
DEVELOPED AT MID PERIOD. REPORTS INDICATE MAGNETIC GRADIENTS ARE
STILL FAIRLY WEAK EXCEPT FOR THE IMMEDIATE VICINITY OF THE DELTA.
THE REMAINING REGIONS HAVE BEEN MOSTLY QUIET.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE
PREDOMINANTLY MODERATE. REGION 8179 IS LARGE AND COMPLEX AND IS
STILL DEVELOPING. CONTINUED M-CLASS ACTIVITY IS LIKELY AND IF
MAGNETIC GRADIENTS STRENGTHEN, X-CLASS ACTIVITY IS POSSIBLE.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 14/2100Z TO 15/2100Z:
THE GEOMAGNETIC FIELD WAS QUIET TO UNSETTLED UNTIL 15/0200Z WHEN
ACTIVE TO MINOR STORMING CONDITIONS DEVELOPED. THE DISTURBANCE ENDED
AT APPROXIMATELY 15/0900Z AND THE FIELD HAS BEEN MOSTLY QUIET TO
UNSETTLED SINCE. THE GREATER THAN 2 MEV ELECTRON FLUX DROPPED BELOW
HIGH LEVELS AT 15/0306Z.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO BE QUIET TO UNSETTLED. ISOLATED PERIODS OF ACTIVE
CONDITIONS ARE POSSIBLE IN HIGH LATITUDES.
III.  EVENT PROBABILITIES 16 MAR-18 MAR
CLASS M    50/50/45
CLASS X    15/15/10
PROTON     15/15/10
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           15 MAR 133
PREDICTED   16 MAR-18 MAR  126/124/122
90 DAY MEAN        15 MAR 095
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 14 MAR  008/010
ESTIMATED AFR/AP 15 MAR  019/019
PREDICTED AFR/AP 16 MAR-18 MAR  010/012-010/008-008/008
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 16 MAR-18 MAR
A.  MIDDLE LATITUDES
ACTIVE                15/15/15
MINOR STORM           05/05/05
MAJOR-SEVERE STORM    01/01/01
B.  HIGH LATITUDES
ACTIVE                20/20/20
MINOR STORM           10/10/10
MAJOR-SEVERE STORM    01/01/01