Viewing archive of Tuesday, 15 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 15 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 258 Issued at 2200Z on 15 SEP 1998IA. Analysis of Solar Active Regions and Activity from 14-2100Z to 15-2100Z
SOLAR ACTIVITY WAS LOW. AN OPTICALLY UNCORRELATED C2
BURST OCCURRED AT 15/0536UT. ALL CURRENT REGIONS APPEAR STABLE OR
DECLINING. MINOR PROMINENCE ACTIVITY WAS REPORTED EARLIER ON THE
EAST LIMB, NEAR THE LOCATION WHERE OLD REGION 8307 (N30, L-034)
RETURNED AS A SIMPLE PLAGE REGION. SEVERAL SMALL PLAGE REGIONS ARE
QUIETLY ROTATING OFF THE DISK.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO REMAIN
AT LOW LEVELS. THERE IS A SLIGHT CHANCE OF INCREASED ACTIVITY FROM
REGIONS DUE TO RETURN IN THE NEXT FEW DAYS, OF PARTICULAR INTEREST
IS REGION 8319 (N19, L-008), DUE BACK ON 17 SEP.
IIA. Geophysical Activity Summary 14-2100Z to 15-2100Z
THE GEOMAGNETIC FIELD HAS BEEN QUIET TO UNSETTLED.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO REMAIN QUIET TO UNSETTLED UNTIL LATE IN THE PERIOD WHEN
THERE IS A CHANCE FOR ACTIVE CONDITIONS RESULTING FROM THE INFLUENCE
OF THE NORTHERN SOLAR CORONAL HOLE.
III. Event Probabilities 16 SEP to 18 SEP
| Class M | 15% | 15% | 15% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 15 SEP 117 Predicted 16 SEP-18 SEP 120/125/130 90 Day Mean 15 SEP 126
V. Geomagnetic A Indices
OBSERVED AFR/AP 14 SEP 002/006 ESTIMATED AFR/AP 15 SEP 007/008 PREDICTED AFR/AP 16 SEP-18 SEP 010/010-010/010-015/020
VI. Geomagnetic Activity Probabilities 16 SEP to 18 SEP
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 20% | 20% | 25% |
| Minor storm | 05% | 05% | 10% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 30% | 30% | 30% |
| Minor storm | 10% | 10% | 15% |
| Major-severe storm | 01% | 01% | 05% |
All times in UTC
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