Viewing archive of Saturday, 12 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 12 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 255 Issued at 2200Z on 12 SEP 1998IA. Analysis of Solar Active Regions and Activity from 11-2100Z to 12-2100Z
SOLAR ACTIVITY WAS LOW. FOUR C-CLASS X-RAY EVENTS
OCCURRED DURING THE PAST 24 HOURS, THE LARGEST AN UNCORRELATED C3 AT
12/0753Z. REGIONS 8331 (N25E02) AND 8333 (N11W71) EACH GENERATED A
SINGLE C1/SF EVENT. REGION 8331 CONTINUES AS THE MOST COMPLEX ACTIVE
REGION ON THE VISIBLE DISK, AS A 25-SPOT 'EAI' BETA GROUP. REGION
8333, WHICH WAS THE SOURCE OF YESTERDAY'S M2/1B EVENT, IS CURRENTLY
A 5-SPOT 'DAO' BETA. NEW REGION 8335 (S22E68), A SMALL C-TYPE
GROUP, WAS NUMBERED TODAY.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE LOW.
IIA. Geophysical Activity Summary 11-2100Z to 12-2100Z
THE GEOMAGNETIC FIELD HAS BEEN QUIET TO UNSETTLED FOR THE PAST 24
HOURS.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO REMAIN QUIET TO UNSETTLED FOR THE NEXT 12-24 HOURS, WITH
CONDITIONS DECREASING TO MOSTLY QUIET ON DAYS 2 AND 3.
III. Event Probabilities 13 SEP to 15 SEP
| Class M | 25% | 25% | 25% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 12 SEP 135 Predicted 13 SEP-15 SEP 130/125/125 90 Day Mean 12 SEP 125
V. Geomagnetic A Indices
OBSERVED AFR/AP 11 SEP 005/005 ESTIMATED AFR/AP 12 SEP 012/009 PREDICTED AFR/AP 13 SEP-15 SEP 010/009-005/009-005/009
VI. Geomagnetic Activity Probabilities 13 SEP to 15 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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