FROM SPACE ENVIRONMENT SERVICES CENTER, BOULDER, COLORADO
SDF NUMBER 261
JOINT USAF/NOAA REPORT OF SOLAR AND GEOPHYSICAL ACTIVITY.
ISSUED 2200Z 17 SEP 1988
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM 16/2100Z
TO 17/2100Z:  SOLAR ACTIVITY HAS BEEN LOW. AN UNCORRELATED,
MINOR TYPE IV SWEEP OCCURRED AT 17/1500Z. TWO UNCORRELATED
C-CLASS XRAY EVENTS OCCURRED AT 17/0043Z AND 17/1402Z. REGIONS
5148 (S13W10) AND 5153 (N23E02) EACH PRODUCED A SUBFLARE DURING
THE PERIOD. NEWLY ASSIGNED REGION 5158 (S35E65), A C-CLASS
GROUP, ROTATED INTO VIEW TODAY ACCOMPANIED BY SURGING TO .08 RV.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE
VERY LOW TO LOW. THERE IS A FAIR CHANCE OF ISOLATED C-CLASS
ACTIVITY.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 16/2100Z TO 17/2100Z:
THE GEOMAGNETIC FIELD HAS BEEN AT UNSETTLED TO ACTIVE LEVELS
FOR THE PAST 24 HOURS AT MIDDLE LATITUDES. THE HIGH LATITUDE
FIELD HAS BEEN AT ACTIVE TO MINOR STORM LEVELS WITH A PERIOD
OF MAJOR STORMING FROM 17/0900-1030Z.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO BE UNSETTLED AT MIDDLE LATITUDES. THE HIGH
LATITUDE FIELD IS EXPECTED TO BE AT MINOR STORM LEVELS ON THE
FIRST DAY DECLINING TO ACTIVE LEVELS FOR THE REMAINDER OF THE
PERIOD BASED ON THE RECURRENT PATTERN OF FIELD ACTIVITY.
III.  EVENT PROBABILITIES 18 SEP-20 SEP
CLASS M    05/05/05
CLASS X    01/01/01
PROTON     01/01/01
PCAF       GREEN
IV.  OTTAWA 10.7 CM FLUX
OBSERVED           17 SEP  133
PREDICTED   18 SEP-20 SEP  136/140/145
90 DAY MEAN        17 SEP  151
V.  GEOMAGNETIC A INDICES
OBSERVED  AFR/AP 16 SEP  007/013
ESTIMATED AFR/AP 17 SEP  018/030
PREDICTED AFR/AP 18 SEP-20 SEP  012/030-010/020-014/025