NOAA/USAF Report of Solar-Geophysical Activity 15 September 2000

:Product: Report of Solar-Geophysical Activity
:Issued: 2000 Sep 15 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 259 ISSUED AT 2200Z ON 15 SEP 2000
IA.  ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM  14/2100Z
TO 15/2100Z:  SOLAR ACTIVITY WAS MODERATE. REGION 9165 (N14E01) WAS
THE MOST PRODUCTIVE SUNSPOT GROUP PRODUCING AN M2/SF AT 15/0532 UTC,
AN M2/1N AT 15/1437 UTC, AND SEVERAL C-CLASS FLARES. THIS AREA
CONTINUES TO GROW IN SUNSPOT AREA AND MAGNETIC COMPLEXITY. REGION
9166 (S14E62) IS THE OTHER DISK AREA OF NOTE AND IS A COMPACT D-TYPE
SUNSPOT GROUP. SO FAR 9166 HAS ONLY PRODUCED LOW-LEVEL C-CLASS
FLARES.
IB.  SOLAR ACTIVITY FORECAST:  SOLAR ACTIVITY IS EXPECTED TO BE
MODERATE. ADDITIONAL M-CLASS FLARES ARE LIKELY IN REGION 9165 AND
C-CLASS FLARES ARE POSSIBLE IN REGION 9166.
IIA.  GEOPHYSICAL ACTIVITY SUMMARY 14/2100Z TO 15/2100Z:
THE GEOMAGNETIC FIELD WAS QUIET TO ACTIVE. A SHOCK IN THE SOLAR WIND
WAS DETECTED BY THE NASA ACE SPACECRAFT AT ABOUT 15/0400 UTC. THE
SHOCK HAD A MODERATELY STRONG INCREASE IN DENSITY BUT ONLY SLIGHT
ENHANCEMENT IN REDIAL SPEED AND TOTAL IMF. BZ WAS STRONGLY POSITIVE
FOR SEVERAL HOURS FOLLOWING THE SHOCK PASSAGE AND HAS JUST TURN
SOUTHWARD AT ABOUT 15/1900 UTC. EVIDENCE SUGGESTS THAT THIS SHOCK IS
ASSOCIATED WITH THE CME AND ERUPTIVE FILAMENT ON SEPTEMBER 12. THE
GREATER THAN 10 MEV PROTON EVENT CONTINUES IN PROGRESS.  THE CURRENT
FLUX (2130 UTC) IS ABOUT 10 PFU AND IS SLOWLY DROPPING.
IIB.  GEOPHYSICAL ACTIVITY FORECAST:  THE GEOMAGNETIC FIELD IS
EXPECTED TO BE PREDOMINATELY QUIET TO UNSETTLED WITH THE POSSIBILITY
OF ISOLATED ACTIVE CONDITIONS AS THE CME STRUCTURE PASSES THE EARTH.
THE GREATER THAN 10 MEV PROTON EVENT IS EXPECTED TO END DURING THE
FIRST DAY OF THE FORECAST PERIOD.
III.  EVENT PROBABILITIES 16 SEP-18 SEP
CLASS M    50/50/50
CLASS X    05/05/05
PROTON     05/01/01
PCAF       IN PROGRESS
IV.  PENTICTON 10.7 CM FLUX
OBSERVED           15 SEP 159
PREDICTED   16 SEP-18 SEP  165/170/175
90 DAY MEAN        15 SEP 177
V.  GEOMAGNETIC A INDICES
OBSERVED AFR/AP 14 SEP  003/006
ESTIMATED AFR/AP 15 SEP  010/009
PREDICTED AFR/AP 16 SEP-18 SEP  010/015-010/010-010/010
VI.  GEOMAGNETIC ACTIVITY PROBABILITIES 16 SEP-18 SEP
A.  MIDDLE LATITUDES
ACTIVE                15/15/15
MINOR STORM           10/10/10
MAJOR-SEVERE STORM    01/01/01
B.  HIGH LATITUDES
ACTIVE                15/15/15
MINOR STORM           10/10/10
MAJOR-SEVERE STORM    01/01/01