:Product: 19991012RSGA.txt
:Issued: 1999 Oct 12 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 285 ISSUED AT 2200Z ON 12 OCT 1999
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  11/2100Z
TO 12/2100Z:  SOLAR ACTIVITY WAS LOW. REGION 8731 (N10E49) PRODUCED
MOST OF TODAY'S LOW LEVEL SUBFLARE ACTIVITY. THE REGION ROTATED MORE
FULLY INTO VIEW AS A MODERATE SIZED D-TYPE GROUP. REGION 8728
(N22E25) CONTINUES TO BE THE LARGEST REGION ON THE DISK BUT WAS
FAIRLY STABLE, EXHIBITING ONLY OCCASIONAL POINT BRIGHTENINGS. NEW
REGION 8732 (N20E41) WAS ASSIGNED TODAY.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE LOW.
THERE IS, HOWEVER, A CHANCE FOR AN ISOLATED M-CLASS EVENT FROM
EITHER REGION 8728 OR 8731.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 11/2100Z TO 12/2100Z:
THE GEOMAGNETIC FIELD RANGED FROM UNSETTLED TO MINOR STORM LEVELS,
WITH AN INTERVAL OF MAJOR STORM AT HIGH LATITUDES FROM 0900-1200Z.
AN INITIALLY ACTIVE LEVEL DISTURBANCE STRENGTHENED TO MOSTLY MINOR
STORM LEVELS FROM 0000-1200Z. CONDITIONS APPEARED TO BE SUBSIDING
DURING THE LAST NINE HOURS OF THE REPORTING INTERVAL (1200-2100Z),
WITH MID-LATITUDES ATTAINING UNSETTLED AND HIGH LATITUDES AT ACTIVE
TO MINOR STORM. THE GREATER THAN 2 MEV ELECTRON FLUXES ATTAINED HIGH
LEVELS DURING THE PAST 24 HOURS.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO BE ACTIVE AT MID-LATITUDES AND ACTIVE TO MINOR STORM AT
HIGH LATITUDES DURING THE NEXT THREE DAYS. THE INCREASE IS EXPECTED
AS A RESULT OF EARTH'S INTERACTION WITH A HIGH-SPEED SOLAR-WIND
STREAM FROM A FAVORABLY POSITIONED CORONAL HOLE.
III.  EVENT PROBABILITIES 13 OCT-15 OCT
CLASS M    30/30/30
CLASS X    05/05/05
PROTON     05/05/05
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           12 OCT 184
PREDICTED   13 OCT-15 OCT  185/190/190
90 DAY MEAN        12 OCT 155
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 11 OCT  018/023
ESTIMATED AFR/AP 12 OCT  027/034
PREDICTED AFR/AP 13 OCT-15 OCT  020/030-020/030-020/025
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 13 OCT-15 OCT
A.  MIDDLE LATITUDES
ACTIVE                45/45/45
MINOR STORM           15/15/15
MAJOR-SEVERE STORM    10/10/10
B.  HIGH LATITUDES
ACTIVE                40/40/40
MINOR STORM           20/20/20
MAJOR-SEVERE STORM    10/10/10