Viewing archive of Tuesday, 28 September 1999
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 1999 Sep 28 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 271 Issued at 2200Z on 28 SEP 1999IA. Analysis of Solar Active Regions and Activity from 27-2100Z to 28-2100Z SOLAR ACTIVITY WAS LOW. ONE NEW REGION WAS NUMBERED:
8711 (N24W31).
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO CONTINUE
TO BE LOW.
IIA. Geophysical Activity Summary 27-2100Z to 28-2100Z
THE GEOMAGNETIC FIELD WAS UNSETTLED TO ACTIVE DUE TO A HIGH SPEED
CORONAL HOLE STREAM. THE GREATER THAN 2 MEV ELECTRON FLUX AT
GEOSYNCHRONOUS ORBIT REACHED HIGH LEVELS AT 28/1330UT AND REMAINED
AT HIGH LEVELS FOR THE REST OF THE PERIOD.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO BE QUIET TO UNSETTLED. THE GREATER THAN 2 MEV ELECTRON
FLUX AT GEOSYNCHRONOUS ORBIT IS EXPECTED TO REMAIN AT MODERATE TO
HIGH LEVELS.
III. Event Probabilities 29 SEP to 01 OCT
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 28 SEP 126 Predicted 29 SEP-01 OCT 125/120/120 90 Day Mean 28 SEP 158
V. Geomagnetic A Indices
OBSERVED AFR/AP 27 SEP 031/037 ESTIMATED AFR/AP 28 SEP 025/018 PREDICTED AFR/AP 29 SEP-01 OCT 015/012-010/012-010/010
VI. Geomagnetic Activity Probabilities 29 SEP to 01 OCT
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 20% | 15% | 15% |
| Minor storm | 10% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 25% | 15% | 15% |
| Minor storm | 15% | 10% | 10% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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