Viewing archive of Thursday, 21 September 2000
Solar activity report
Any mentioned solar flare in this report has a scaling factor applied by the Space Weather Prediction Center (SWPC). Because of the SWPC scaling factor, solar flares are reported as 42% smaller than for the science quality data. The scaling factor has been removed from our archived solar flare data to reflect the true physical units.
Report of Solar-Geophysical Activity 2000 Sep 21 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 265 Issued at 2200Z on 21 SEP 2000IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z
SOLAR ACTIVITY HAS BEEN LOW. ONLY LOW C-CLASS EVENTS
OCCURRED THROUGH THE PERIOD. AN EIGHT DEGREE FILAMENT DISAPPEARED
AT N33E14 BETWEEN 20/1525 UTC AND 21/0706 UTC. REGION 9169 (N09E32)
REMAINS A BETA-GAMMA-DELTA MAGNETIC CONFIGURATION. A NEW REGION WAS
NUMBERED TODAY AS REGION 9170 (S07E28).
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE LOW
TO MODERATE. ISOLATED MAJOR FLARING REMAINS A POSSIBILITY WITH
REGION 9169.
IIA. GEOPHYSICAL ACTIVITY SUMMARY 20/2100Z TO 21/2100Z:
THE GEOMAGNETIC FIELD WAS QUIET TO UNSETTLED. THE GREATER THAN 2 MEV
ELECTRON FLUX AT GEOSYNCHRONOUS ORBIT REACHED MODERATE DURING THE
PERIOD.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO BE QUIET TO UNSETTLED THROUGH THE PERIOD.
III. Event Probabilities 22 SEP to 24 SEP
| Class M | 70% | 70% | 70% |
| Class X | 25% | 25% | 25% |
| Proton | 05% | 05% | 05% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 21 SEP 225 Predicted 22 SEP-24 SEP 230/235/235 90 Day Mean 21 SEP 178
V. Geomagnetic A Indices
OBSERVED AFR/AP 20 SEP 012/013 ESTIMATED AFR/AP 21 SEP 010/010 PREDICTED AFR/AP 22 SEP-24 SEP 010/010-010/010-010/010
VI. Geomagnetic Activity Probabilities 22 SEP to 24 SEP
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 20% | 20% | 20% |
| Minor storm | 10% | 10% | 10% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 25% | 25% | 25% |
| Minor storm | 10% | 10% | 10% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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