Viewing archive of Saturday, 21 February 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 Feb 21 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 052 Issued at 2200Z on 21 FEB 1998IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z SOLAR ACTIVITY WAS VERY LOW. ISOLATED B-CLASS X-RAY
BURSTS WERE DETECTED WITH NO OPTICAL ASSOCIATIONS. REGION 8156 (S25
W72) APPEARED TO BE IN A PERIOD OF GRADUAL DECAY, LOSING A FEW
SPOTS. NEW REGION 8162 (S32E46), A SMALL, STABLE B-CLASS GROUP, WAS
NUMBERED. A CORONAL MASS EJECTION (CME) WAS DETECTED BEGINNING
AROUND 21/0200UT. MOST OF THE MASS WAS SEEN DEPARTING THE WEST LIMB,
SLIGHTLY DECLINED TO THE ECLIPTIC.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE VERY
LOW TO LOW WITH REGION 8156 PROVIDING A FAIR CHANCE FOR AN ISOLATED
C-CLASS SUBFLARE.
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
THE GEOMAGNETIC FIELD WAS QUIET AT ALL LATITUDES. THE GREATER THAN 2
MEV ELECTRON FLUX INCREASED TO HIGH LEVELS BEGINNING 21/1812UT.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS
EXPECTED TO BE MOSTLY QUIET THROUGH 23 FEBRUARY. ACTIVITY IS
EXPECTED TO INCREASE TO UNSETTLED LEVELS ON THE FINAL DAY OF THE
FORECAST PERIOD. THE GREATER THAN 2 MEV ELECTRON FLUX IS EXPECTED TO
DECLINE TO MODERATE TO NORMAL LEVELS EARLY IN THE PERIOD.
III. Event Probabilities 22 FEB to 24 FEB
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | GREEN | ||
IV. Penticton 10.7 cm Flux
Observed 21 FEB 095 Predicted 22 FEB-24 FEB 094/092/090 90 Day Mean 21 FEB 096
V. Geomagnetic A Indices
OBSERVED AFR/AP 20 FEB 008/007 ESTIMATED AFR/AP 21 FEB 002/005 PREDICTED AFR/AP 22 FEB-24 FEB 005/008-005/005-008/008
VI. Geomagnetic Activity Probabilities 22 FEB to 24 FEB
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 10% | 10% | 20% |
| Minor storm | 05% | 05% | 10% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 10% | 10% | 25% |
| Minor storm | 05% | 05% | 15% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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