Viewing archive of Wednesday, 15 April 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 Apr 15 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 105 Issued at 2200Z on 15 APR 1998IA. Analysis of Solar Active Regions and Activity from 14-2100Z to 15-2100Z
SOLAR ACTIVITY WAS LOW. REGION 8203 (N31W24) GREW IN
WHITE LIGHT AND H-ALPHA AND IS NOW A SMALL D-TYPE SUNSPOT GROUP WITH
EMBEDDED ARCH-FILAMENTS. THE REGION PRODUCED A C8/SF AT 0746Z, A
C8/SF AT 1233Z, AND TOGETHER WITH REGION 8198 (S29W31), A C9 X-RAY
BURST AT 1511Z. FREQUENT DISCRETE RADIO BURSTS OCCURRED EARLY IN THE
PERIOD. THE REST OF THE DISK AND LIMBS WERE QUIET.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE LOW
TO MODERATE, WITH REGION 8203 THE MAIN ACTIVE CENTER.
IIA. Geophysical Activity Summary 14-2100Z to 15-2100Z
THE GEOMAGNETIC FIELD WAS QUIET TO UNSETTLED.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO BE QUIET TO UNSETTLED THROUGHOUT THE INTERVAL.
III. Event Probabilities 16 APR to 18 APR
| Class M | 50% | 50% | 50% |
| Class X | 05% | 05% | 05% |
| Proton | 05% | 05% | 05% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 15 APR 113 Predicted 16 APR-18 APR 110/110/105 90 Day Mean 15 APR 104
V. Geomagnetic A Indices
OBSERVED AFR/AP 14 APR 006/008 ESTIMATED AFR/AP 15 APR 005/008 PREDICTED AFR/AP 16 APR-18 APR 010/008-015/012-010/010
VI. Geomagnetic Activity Probabilities 16 APR to 18 APR
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 10% | 20% | 10% |
| Minor storm | 05% | 10% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 25% | 15% |
| Minor storm | 05% | 10% | 05% |
| Major-severe storm | 01% | 01% | 01% |
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