Viewing archive of Sunday, 26 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 26 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 269 Issued at 2200Z on 26 SEP 1999IA. Analysis of Solar Active Regions and Activity from 25-2100Z to 26-2100Z SOLAR ACTIVITY WAS LOW DUE TO A SINGLE C-CLASS EVENT,
AN UNCORRELATED C1 X-RAY FLARE AT 26/0033UT. ACTIVITY FOR THE REST
OF THE PERIOD WAS VERY LOW.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE VERY
LOW TO LOW.
IIA. Geophysical Activity Summary 25-2100Z to 26-2100Z
THE GEOMAGNETIC FIELD WAS MOSTLY QUIET TO UNSETTLED WITH A PERIOD OF
MINOR STORMING FROM 26/15-1800UT.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO BE QUIET TO ACTIVE FOR THE FIRST DAY OF THE FORECAST
PERIOD AND QUIET TO UNSETTLED FOR THE REMAINDER OF THE PERIOD.
III. Event Probabilities 27 SEP to 29 SEP
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 26 SEP 123 Predicted 27 SEP-29 SEP 120/120/115 90 Day Mean 26 SEP 160
V. Geomagnetic A Indices
OBSERVED AFR/AP 25 SEP 001/004 ESTIMATED AFR/AP 26 SEP 010/010 PREDICTED AFR/AP 27 SEP-29 SEP 015/020-010/012-010/008
VI. Geomagnetic Activity Probabilities 27 SEP to 29 SEP
| 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% |
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