:Product: 20000406RSGA.txt
:Issued: 2000 Apr 06 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 097 ISSUED AT 2200Z ON 06 APR 2000
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  05/2100Z
TO 06/2100Z:  SOLAR ACTIVITY WAS MODERATE.  REGION 8948 (S12E42)
PRODUCED AN M1/2B FLARE AT 06/0229UT.  THIS EVENT WAS ACCOMPANIED BY
A MINOR RADIO BURST AND A TYPE II SWEEP (ESTIMATE SHOCK VELOCITY OF
700KM/S).    REGION 8948 RETAINS SOME MAGNETIC COMPLEXITY, BUT IT
AND MOST OF THE OTHER 11 SPOTTED REGIONS ON THE DISK APPEAR TO BE
SLOWLY DECLINING.   REGION 8933 (N19W96) HAS QUIETLY ROTATED OFF THE
DISK.  THE SMALL FILAMENT NEAR S15 E10 DISAPPEARED EARLY TODAY.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE LOW
TO MODERATE.  RETURNING REGION 8910 (N13 L=069), A MAJOR FLARE
PRODUCER LAST ROTATION,  IS DUE BACK ON THE EAST LIMB LATE TOMORROW.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY FROM 05/2100Z TO 06/2100Z:
THE GEOMAGNETIC FIELD RANGED FROM UNSETTLED TO MAJOR STORM LEVELS.  A
SHOCK WAS OBSERVED BY THE ACE SPACECRAFT AROUND 06/1600UT.  THE
ASSOCIATED SUDDEN IMPULSE WAS OBSERVED AT  1640UT (37NT AS OBSERVED
AT SAN JUAN) AND THE FIELD HAS BEEN AT MAJOR STORM LEVELS SINCE THAT
TIME.  THERE WERE MAGNETOPAUSE CROSSINGS OBSERVED ON BOTH GOES 8 AND
GOES 10 STARTING AROUND 1800UT.  THIS DISTURBANCE IS MOST LIKELY THE
CONSEQUENCE OF THE HALO CME OBSERVED FOLLOWING THE C9/2F FLARE AT
04/1541UT.  THE SATELLITE PROTON EVENT WHICH BEGAN AT 04/2055UT,
ENDED TODAY AT 0155UT.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO BE AT STORM LEVELS FOR MUCH OF TOMORROW.  THE FIELD IS
EXPECTED TO RETURN TO UNSETTLED LEVELS BY THE END OF THE PERIOD.
III.  EVENT PROBABILITIES 07 APR-09 APR
CLASS M    50/50/50
CLASS X    05/05/05
PROTON     05/05/05
PCAF       GREEN
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           06 APR 178
PREDICTED   07 APR-09 APR  175/180/180
90 DAY MEAN        06 APR 185
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 05 APR  014/012
ESTIMATED AFR/AP 06 APR  030/033
PREDICTED AFR/AP 07 APR-09 APR  025/030-010/020-008/015
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 07 APR-09 APR
A.  MIDDLE LATITUDES
ACTIVE                35/15/15
MINOR STORM           35/10/10
MAJOR-SEVERE STORM    11/01/01
B.  HIGH LATITUDES
ACTIVE                30/40/20
MINOR STORM           40/20/10
MAJOR-SEVERE STORM    06/01/01