FROM SPACE ENVIRONMENT SERVICES CENTER, BOULDER, COLORADO
SDF NUMBER 269
JOINT USAF/NOAA REPORT OF SOLAR AND GEOPHYSICAL ACTIVITY.
ISSUED 2200Z 25 SEP 1988
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM 24/2100Z
TO 25/2100Z:  SOLAR ACTIVITY WAS MODERATE.  REGION 5169 (S21E48)
PRODUCED THE SOLE M-CLASS EVENT IN THE PAST 24 HOURS, AN M2/2B
AT 0050Z.  A BURST OF 710 FLUX UNITS AT 10 CM. AND TYPE II AND
IV SWEEP WERE ASSOCIATED WITH THE FLARE. A LARGE CME ACCOMPAN-
IED THE ACTIVITY. THIS VERY ORDINARY LOOKING REGION HAS BEEN
QUIET SINCE. SURGING OCCURRED NEAR S24E90 WHILE THE WEST LIMB
WAS QUIET.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE
LOW TO MODERATE. AN ISOLATED M-CLASS FLARE IS LIKELY TO OCCUR
DURING THE FORECAST PERIOD.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 24/2100Z TO 25/2100Z:
THE GEOMAGNETIC FIELD HAS BEEN GENERALLY UNSETTLED AT MID-
LATITUDES.  HIGH LATITUDES OBSERVED MOSTLY ACTIVE
CONDITIONS AFTER A STINT OF MAJOR STORM LEVELS EARLY IN
THE DAY.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD
SHOULD BE UNSETTLED TO ACTIVE THE NEXT 24 HOURS. A CORONAL
HOLE-INDUCED DISTURBANCE IS EXPECTED 27 SEPT. AND THEN
SLOWLY WANE THROUGH THE END OF THE INTERVAL.
III.  EVENT PROBABILITIES 26 SEP-28 SEP
CLASS M    40/40/40
CLASS X    10/10/10
PROTON     10/10/10
PCAF       GREEN
IV.  OTTAWA 10.7 CM FLUX
OBSERVED           25 SEP  177
PREDICTED   26 SEP-28 SEP  175/173/168
90 DAY MEAN        25 SEP  153
V.  GEOMAGNETIC A INDICES
OBSERVED  AFR/AP 24 SEP  007/013
ESTIMATED AFR/AP 25 SEP  009/025
PREDICTED AFR/AP 26 SEP-28 SEP  015/025-020/040-010/030