Report of Solar-Geophysical Activity
:Issued: 2000 May 10 2200 UT
# 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 131 ISSUED AT 2200Z ON 10 MAY 2000
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  09/2100Z
TO 10/2100Z:  SOLAR ACTIVITY WAS LOW. THE MOST IMPRESSIVE EVENT OF
THE PERIOD BEGAN WITH THE ERUPTION OF A 5 DEGREE FILAMENT FROM
N14E16.  IT WAS SOON FOLLOWED BY A LONG-DURATION 2N/C8 FLARE FROM
REGION 8990 (N14E20) AT 10/1941Z AS WELL AS TYPE II (680 KM/S) AND
TYPE IV RADIO SWEEPS.  NEW REGION 8993 (S23W06) WAS NUMBERED TODAY,
CORRECTING AN EARLIER ERROR.  THE PREVIOUS TWO DAYS IT WAS
INCORRECTLY REFERRED TO AS REGION 8986, WHICH HAD ACTUALLY
DISSIPATED. REGION 8994 (N11W01) WAS ALSO NUMBERED.  TODAY'S
PENTICTON 10CM FLUX VALUE WAS LIKELY FLARE ENHANCED.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE LOW
TO MODERATE.  REGIONS 8989 (N16W01), 8990 (N14E20), AND 8991
(N15E46) ARE ALL CAPABLE OF PRODUCING M FLARES.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 09/2100Z TO 10/2100Z:
THE GEOMAGNETIC FIELD WAS QUIET.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO REMAIN QUIET TO UNSETTLED THROUGH THE BEGINNING OF THE
PERIOD.  THE ONSET OF A GEOMAGNETIC STORM IS EXPECTED LATE 11 MAY TO
EARLY 12 MAY DUE TO A FILAMENT ERUPTION AND PARTIAL HALO CME
OBSERVED ON 8 MAY.  ALTHOUGH, AT THIS POINT, THERE IS NO INDICATION
OF AN APPROACHING SHOCK IN THE ACE DATA.  EFFECTS OF A RECURRENT
CORONAL HOLE WILL EXTEND THE ACTIVE TO MINOR STORM CONDITIONS
THROUGH 13 MAY.
III.  EVENT PROBABILITIES 11 MAY-13 MAY
CLASS M    50/50/50
CLASS X    05/05/05
PROTON     05/05/05
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           10 MAY 179
PREDICTED   11 MAY-13 MAY  165/170/175
90 DAY MEAN        10 MAY 186
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 09 MAY  007/011
ESTIMATED AFR/AP 10 MAY  005/007
PREDICTED AFR/AP 11 MAY-13 MAY  015/015-030/025-020/025
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 11 MAY-13 MAY
A.  MIDDLE LATITUDES
ACTIVE                30/30/30
MINOR STORM           15/30/20
MAJOR-SEVERE STORM    05/10/05
B.  HIGH LATITUDES
ACTIVE                30/30/30
MINOR STORM           25/40/35
MAJOR-SEVERE STORM    05/10/05