Viewing archive of Sunday, 13 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 13 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 256 Issued at 2200Z on 13 SEP 1998IA. Analysis of Solar Active Regions and Activity from 12-2100Z to 13-2100Z SOLAR ACTIVITY WAS LOW. FIVE C-CLASS X-RAY EVENTS
OCCURRED DURING THE PAST 24 HOURS, THE LARGEST A C8/SF FROM REGION
8333 (N12W83) AT 13/1825Z. THIS REGION, A 3-SPOT 'DAO' BETA GROUP AS
IT APPROACHES THE WEST LIMB, WAS ALSO THE SOURCE OF AN EARLIER C1/SF
EVENT. REGION 8329 (N14W60) PRODUCED A C3/SF EVENT AT 13/0907Z, AND
UNSPOTTED REGION 8326 (N21W53) GENERATED IT'S SECOND C1/SF EVENT
SINCE 2030Z YESTERDAY.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO REMAIN
LOW.
IIA. Geophysical Activity Summary 12-2100Z to 13-2100Z
THE GEOMAGNETIC FIELD HAS BEEN MOSTLY QUIET FOR THE PAST 24 HOURS,
WITH ISOLATED PERIODS OF UNSETTLED CONDITIONS RECORDED AT HIGH
LATITUDES.
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 14 SEP to 16 SEP
| Class M | 25% | 25% | 25% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 13 SEP 131 Predicted 14 SEP-16 SEP 125/125/130 90 Day Mean 13 SEP 126
V. Geomagnetic A Indices
OBSERVED AFR/AP 12 SEP 009/012 ESTIMATED AFR/AP 13 SEP 007/009 PREDICTED AFR/AP 14 SEP-16 SEP 005/009-005/009-010/012
VI. Geomagnetic Activity Probabilities 14 SEP to 16 SEP
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 05% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 05% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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