NOAA/USAF Report of Solar-Geophysical Activity 6 September 2000
:Product: Report of Solar-Geophysical Activity
:Issued: 2000 Sep 06 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 250 ISSUED AT 2200Z ON 06 SEP 2000
IA. ANALYSIS OF SOLAR ACTIVE REGIONS AND ACTIVITY FROM 05/2100Z
TO 06/2100Z: SOLAR ACTIVITY CONTINUED AT LOW LEVELS. REGION 9154
(S18W21) REMAINED MODERATE IN SIZE AND MAGNETIC COMPLEXITY AND
PRODUCED OCCASIONAL C-CLASS SUBFLARES. REGION 9149 (N13W49) ALSO
REMAINED MODERATE IN SIZE AND COMPLEXITY, BUT PRODUCED NO FLARES.
THE REMAINING REGIONS WERE SIMPLE AND STABLE. NEW REGIONS 9156
(S27E49) AND 9157 (N21E63) WERE NUMBERED.
IB. SOLAR ACTIVITY FORECAST: LOW TO MODERATE ACTIVITY IS EXPECTED.
REGIONS 9154 AND 9149 COULD PRODUCE ISOLATED M-CLASS FLARES.
IIA. GEOPHYSICAL ACTIVITY SUMMARY 05/2100Z TO 06/2100Z:
GEOMAGNETIC FIELD ACTIVITY WAS AT QUIET TO UNSETTLED LEVELS UNTIL
ABOUT 06/1700 UTC. ACE REAL TIME SOLAR WIND MEASUREMENTS INDICATED
AN INTERPLANETARY SHOCK PASSAGE AT L1 AT ABOUT 06/1614 UTC FOLLOWED
BY A SUDDEN IMPULSE AT 06/1704 UTC (16 NT, AS MEASURED BY THE
BOULDER USGS MAGNETOMETER). FIELD ACTIVITY INCREASED TO UNSETTLED TO
ACTIVE LEVELS FOLLOWING THE IMPULSE. THIS ACTIVITY IS LIKELY
ASSOCIATED WITH A LARGE FILAMENT DISAPPEARANCE/PARTIAL-HALO CME
OBSERVED ON 4 SEPTEMBER. THE GREATER THAN 2 MEV ELECTRON FLUX AT
GEOSYNCHRONOUS ORBIT MAY REACH MODERATE TO HIGH LEVELS DURING THE
LATTER HALF OF THE PERIOD.
IIB. GEOPHYSICAL ACTIVITY FORECAST: GEOMAGNETIC FIELD ACTIVITY IS
EXPECTED TO BE AT UNSETTLED TO MINOR STORM LEVELS DURING THE FIRST
HALF OF THE PERIOD AS THE CME-RELATED DISTURBANCE CONTINUES. FIELD
ACTIVITY IS EXPECTED TO DECREASE TO UNSETTLED LEVELS DURING THE
LATTER HALF OF THE PERIOD AS THE DISTURBANCE SUBSIDES.
III. EVENT PROBABILITIES 07 SEP-09 SEP
CLASS M 30/30/30
CLASS X 05/05/05
PROTON 05/05/05
PCAF GREEN
IV. PENTICTON 10.7 CM FLUX
OBSERVED 06 SEP 179
PREDICTED 07 SEP-09 SEP 185/190/190
90 DAY MEAN 06 SEP 181
V. GEOMAGNETIC A INDICES
OBSERVED AFR/AP 05 SEP 008/008
ESTIMATED AFR/AP 06 SEP 010/010
PREDICTED AFR/AP 07 SEP-09 SEP 030/030-020/020-015/015
VI. GEOMAGNETIC ACTIVITY PROBABILITIES 07 SEP-09 SEP
A. MIDDLE LATITUDES
ACTIVE 20/30/25
MINOR STORM 30/20/10
MAJOR-SEVERE STORM 15/10/05
B. HIGH LATITUDES
ACTIVE 25/35/30
MINOR STORM 35/25/15
MAJOR-SEVERE STORM 20/15/10