FROM SPACE ENVIRONMENT SERVICES CENTER, BOULDER, COLORADO
SDF NUMBER 176
JOINT USAF/NOAA REPORT OF SOLAR AND GEOPHYSICAL ACTIVITY.
ISSUED 2200Z 24 JUN 1988
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM 23/2100Z
TO 24/2100Z:  SOLAR ACTIVITY HAS BEEN HIGH. REGION 5047 (S16W55)
PRODUCED THREE X-CLASS X-RAY FLARES DURING THE PERIOD: AN X1/1B
AT 0430Z, AN X2/2B AT 1609Z, AND AN X5/1B AT 1648Z. THE REGION
CONTINUES TO BE VERY IMPRESSIVE WITH TWO DELTA CONFIGURATIONS,
STRONG GRADIENTS AND EVIDENCE OF STRONG MAGNETIC SHEAR. THE X5
FLARE WAS MANIFEST AS A WHITE LIGHT FLARE AND LASTED FOR 91
MINUTES. STRONG DISCRETE FREQUENCY RADIO BURSTS (17000 SFU AT
245MHZ AND 340 SFU AT 2695MHZ) AND A STRONG TYPE IV RADIO SWEEP
ACCOMPANIED THE EVENT. REGION 5051 (N37W63) PRODUCED SOME
SMALL FLARES: THE LARGEST OF WHICH WAS A C7.4/SF AT 1414Z
WHICH WAS TIME CORRELATED WITH A TYPE II RADIO SWEEP. NEW
REGION 5059 (N16E39) WAS ASSIGNED TODAY. SURGE ACTIVITY HAS
BEEN REPORTED ON THE EAST LIMB AT ABOUT S20, CLOSE TO THE
LATITUDE OF REGION 5058 (S18E63). THE REMAINDER OF THE SOLAR
DISK AND LIMBS WERE QUIET AND STABLE.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE
MODERATE TO HIGH. REGION 5047 IS EXPECTED TO KEEP ACTIVITY UP
TO AT LEAST MODERATE LEVELS AND HAS A FAIR TO GOOD CHANCE OF
PRODUCING ADDITIONAL X-CLASS FLARES. DUE TO THE POSITIONING OF
OF THE REGION THERE IS A FAIR TO GOOD CHANCE THAT AN EVENT
LEVEL FLARE COULD PRODUCE A PROTON EVENT.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 23/2100Z TO 24/2100Z:
THE GEOMAGNETIC FIELD HAS BEEN AT UNSETTLED TO ACTIVE LEVELS
AT MIDDLE LATITUDES AND WAS AT ACTIVE TO MINOR STORM LEVELS
AT HIGH LATITUDES. A SUDDEN IMPULSE OF 33 GAMMA WAS OBSERVED
AT 0028Z. A MAGNETIC CROCHET WAS OBSERVED IN BOULDER AND WAS
ASSOCIATED THE X5 FLARE MENTIONED ABOVE. THE CURRENT DISTUR-
BANCE IS PROBABLY BEING CAUSED BY THE CORONAL HOLE LOCATED
IN THE SOUTHWEST SOLAR QUADRANT. FLARE ACTIVITY FROM 23 MAY
MAY ALSO BE A CONTRIBUTING FACTOR.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO CONTINUE TOMORROW AT UNSETTLED TO ACTIVE LEVELS WITH
PERIODS OF MINOR STORM CONDITIONS AT HIGH LATITUDES. AN INCREASE
IN ACTIVITY TO MINOR TO MAJOR STORM LEVELS IS EXPECTED SOMETIME
ON THE SECOND DAY AND CONTINUING THROUGH THE THIRD DAY IN RES-
PONSE TO TODAY'S SOLAR FLARE. A PROTON EVENT IS EXPECTED EARLY
ON THE FIRST DAY AS WELL: GREATER THAN 10MEV PARTICLES ARE
CURRENTLY PREDICTED TO PEAK AT ABOUT 300 PARTICLES/CM2/S/STER.
III.  EVENT PROBABILITIES 25 JUN-27 JUN
CLASS M    95/95/95
CLASS X    50/50/50
PROTON     60/60/60
PCAF       RED
IV.  OTTAWA 10.7 CM FLUX
OBSERVED           24 JUN  135
PREDICTED   25 JUN-27 JUN  135/135/133
90 DAY MEAN        24 JUN  124
V.  GEOMAGNETIC A INDICES
OBSERVED  AFR/AP 23 JUN  008/017
ESTIMATED AFR/AP 24 JUN  017/035
PREDICTED AFR/AP 25 JUN-27 JUN  015/035-020/050-051/065