Viewing archive of Monday, 17 August 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 Aug 17 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 229 Issued at 2200Z on 17 AUG 1998IA. Analysis of Solar Active Regions and Activity from 16-2100Z to 17-2100Z SOLAR ACTIVITY WAS LOW. SEVERAL UNCORRELATED C-CLASS
X-RAY FLARES OCCURRED. REGIONS 8280 AND 8282 ARE EXPECTED TO RETURN
IN THE NEXT 24 HOURS. OPTICAL AND X-RAY SENSORS INDICATE THAT 8282
IS LARGE AND ENERGETIC. REGION 8280 ALSO HAS A SIGNIFICANT X-RAY
SIGNATURE.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE LOW
TO MODERATE.
IIA. Geophysical Activity Summary 16-2100Z to 17-2100Z
THE GEOMAGNETIC FIELD WAS QUIET.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO REMAIN QUIET TO UNSETTLED FOR TOMORROW. DURING THE REST
OF THE PERIOD, THE ACTIVITY IS EXPECTED TO CLIMB TO ACTIVE TO MINOR
STORM AS A CORONAL HOLE ROTATES INTO A GEO-EFFECTIVE POSITION.
III. Event Probabilities 18 AUG to 20 AUG
| Class M | 50% | 50% | 50% |
| Class X | 25% | 25% | 25% |
| Proton | 05% | 05% | 05% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 17 AUG 136 Predicted 18 AUG-20 AUG 138/142/137 90 Day Mean 17 AUG 113
V. Geomagnetic A Indices
OBSERVED AFR/AP 16 AUG 001/005 ESTIMATED AFR/AP 17 AUG 004/010 PREDICTED AFR/AP 18 AUG-20 AUG 005/010-010/015-015/020
VI. Geomagnetic Activity Probabilities 18 AUG to 20 AUG
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 05% | 10% | 20% |
| Minor storm | 05% | 05% | 10% |
| Major-severe storm | 01% | 01% | 05% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 05% | 15% | 25% |
| Minor storm | 05% | 05% | 10% |
| Major-severe storm | 01% | 01% | 05% |
All times in UTC
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