:Product: 19980121RSGA.txt
:Issued: 1998 Jan 21 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 021 ISSUED AT 2200Z ON 21 JAN 1998
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  20/2100Z
TO 21/2100Z:  SOLAR ACTIVITY BECAME VERY LOW. ONLY SMALL TO MID
B-CLASS FLARES WERE OBSERVED.  A MODERATELY LARGE FILAMENT LOCATED
NEAR S57E19 FADED BETWEEN 21/0400-0603Z. THIS EVENT WAS ACCOMPANIED
BY A LONG DURATION ARCADE IN THE EUV AND A PARTIAL HALO CORONAL MASS
EJECTION. MOST OF THE HALO OF MATERIAL WAS VISIBLE AROUND THE SOUTH
POLE BUT SOME WAS SEEN INTO NORTHERN LATITUDES AND PRESUMABLY INTO
AND ABOVE THE ECLIPTIC PLANE.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY SHOULD CONTINUE AT A
VERY LOW LEVEL FOR THE NEXT THREE DAYS.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 20/2100Z TO 21/2100Z:
THE GEOMAGNETIC FIELD WAS PREDOMINANTLY QUIET TO UNSETTLED. BRIEF
ACTIVE CONDITIONS WERE OBSERVED FROM 21/0600-0900Z. NEAR THE END OF
THE REPORTING PERIOD, SOLAR WIND VELOCITIES DROPPED FROM
APPROXIMATELY 450 KM/S TO NEAR 350 KM/S.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD SHOULD BE
QUIET TO UNSETTLED FOR 22-23 JAN. UNSETTLED TO ACTIVE CONDITIONS ARE
EXPECTED EARLY ON 24 JAN IN RESPONSE TO THE HALO CME MENTIONED
ABOVE. BRIEF MINOR STORM PERIODS ARE POSSIBLE ON THAT DAY.
III.  EVENT PROBABILITIES 22 JAN-24 JAN
CLASS M    01/01/01
CLASS X    01/01/01
PROTON     01/01/01
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           21 JAN 091
PREDICTED   22 JAN-24 JAN  090/089/088
90 DAY MEAN        21 JAN 096
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 20 JAN  008/011
ESTIMATED AFR/AP 21 JAN  008/010
PREDICTED AFR/AP 22 JAN-24 JAN  008/010-008/008-015/012
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 22 JAN-24 JAN
A.  MIDDLE LATITUDES
ACTIVE                15/10/35
MINOR STORM           05/05/20
MAJOR-SEVERE STORM    01/01/10
B.  HIGH LATITUDES
ACTIVE                15/10/35
MINOR STORM           05/05/25
MAJOR-SEVERE STORM    01/01/10