Viewing archive of Sunday, 20 December 1998
Geophysical 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.
Solar and Geophysical Activity Summary 1998 Dec 20 0245 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Solar and Geophysical Activity Summary
SGAS Number 354 Issued at 0245Z on 20 DEC 1998 This report is compiled from data received at SWO on 19 DECA. Energetic Events
Begin Max End Rgn Loc Xray Op 245MHz 10cm Sweep 0837 0837 0838 110 1055 1055 1055 100 1151 1151 1151 530
B. Proton Events
None
C. Geomagnetic Activity Summary
THE GEOMAGNETIC FIELD WAS QUIET.
SOLAR WIND PARAMETERS WERE VARIABLE (TOTAL FIELD AND DENSITY
INCREASES AND PERIODS OF BZ SOUTHWARD) AT THE END OF THE PERIOD BUT
HAD LITTLE EFFECT ON THE FIELD.
D. Stratwarm
STRATWARM ALERT/SATURDAY/STRATWARM EXISTS.
MAJOR WARMING EXISTS.
THE STRONG ANTICYCLONE OVER CANADIAN ARCTIC CONTINUES. THE
INTENSE WARMING OVER POLAR REGION SLIGHTLY WEAKENING.
THE MAIN VORTEX DISPLACED OVER SOUTHERN URAL AREA AND THE
SECOND WEAKER VORTEX EXISTS OVER LABRADOR, TODAY.
MEAN ZONAL WIND AT 60 N IS FROM EAST ( 15 M/S ) AT 10 HPA
AND ABOVE IN THE UPPER STRATOSPHERE AND TEMPERATURE GRADIENT
REVERSED BETWEEN 60 N AND THE POLE IN THE WHOLE STRATOSPHERE
BELOW 2 HPA.
FU
E. Daily Indices: (real-time preliminary/estimated values)
10 CM 138 SSN 088 AFR/AP 003/007 X-RAY BACKGROUND B8.7 DAILY PROTON FLUENCE (FLUX ACCUMULATION OVER 24 HRS) GT 1 MEV 7.7E+05 GT 10 MEV 1.6E+04 P/(CM2-STER-DAY) (GOES-8 SATELLITE SYNCHRONOUS ORBIT W75 DEGREES) DAILY ELECTRON FLUENCE GT 2 MEV 7.20E+06 E/(CM2-STER-DAY) (GOES-8 SATELLITE SYNCHRONOUS ORBIT W75 DEGREES) 3 HOUR K-INDICES: BOULDER 1 0 0 1 2 2 1 2 PLANETARY 1 1 0 1 2 3 2 3
F. Comments
None
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