Viewing archive of Friday, 11 September 1998
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 1998 Sep 11 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 254 Issued at 2200Z on 11 SEP 1998IA. Analysis of Solar Active Regions and Activity from 10-2100Z to 11-2100Z SOLAR ACTIVITY WAS MODERATE. REGION 8333 (N12W55)
GENERATED A M2/1B X-RAY EVENT AT 11/1603Z, WHICH WAS PRECEEDED BY
TWO EARLIER C1/SF EVENTS, AND FOLLOWED BY A C2/SF EVENT. THE M2
FLARE OCCURRED OVER SEVERAL ERUPTIVE CENTERS, AND HAD AN ASSOCIATED
HIGH SPEED BSD (BRIGHT SURGE ON THE DISK). A SMALL ARCH FILAMENT
SYSTEM IS CURRENTLY IN PLACE OVER THE NORTH PORTION OF THE REGION.
REGION 8333 IS CLASSIFIED AS A 9-SPOT 'CSO' BETA GROUP. ONE NEW
SMALL B-TYPE REGION WAS NUMBERED TODAY, 8334 AT S25W35.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE LOW,
WITH THE CHANCE FOR ANOTHER ISOLATED M-CLASS EVENT FROM REGION 8333.
IIA. Geophysical Activity Summary 10-2100Z to 11-2100Z
THE GEOMAGNETIC FIELD HAS BEEN QUIET AT ALL LATITUDES FOR THE PAST 24
HOURS. THE GREATER THAN 2 MEV ELECTRON FLUX WAS IN THE MODERATE TO
HIGH RANGE.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO BE MOSTLY QUIET, WITH ISOLATED PERIODS OF UNSETTLED
CONDITIONS, FOR THE NEXT THREE DAYS.
III. Event Probabilities 12 SEP to 14 SEP
| Class M | 20% | 15% | 10% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 11 SEP 139 Predicted 12 SEP-14 SEP 135/130/125 90 Day Mean 11 SEP 125
V. Geomagnetic A Indices
OBSERVED AFR/AP 10 SEP 005/005 ESTIMATED AFR/AP 11 SEP 005/005 PREDICTED AFR/AP 12 SEP-14 SEP 010/009-010/009-005/009
VI. Geomagnetic Activity Probabilities 12 SEP to 14 SEP
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 10% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 10% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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