Viewing archive of Thursday, 16 December 1999

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 1999 Dec 16 2200 UTC
Prepared by the NOAA © SWPC and processed by SpaceWeatherLive.com

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 350 Issued at 2200Z on 16 DEC 1999

IA. Analysis of Solar Active Regions and Activity from 15-2100Z to 16-2100Z

SOLAR ACTIVITY WAS LOW. SEVERAL LOW-LEVEL C-CLASS FLARES OCCURRED DURING THE PERIOD. REGION 8799 HAS MERGED WITH REGION 8798 (S14E34) AND IS NOW PART OF THAT ONE REGION. REGION 8798 IS THE LARGEST REGION ON THE SOLAR DISK WITH AN AREA OF 410 MILLIONTHS. IN WHITE LIGHT REGION 8798 HAS A COMPLEX APPEARANCE BUT REMAINS MAGNETICALLY CLASSIFIED AS A BETA GROUP. AN OPTICALLY UNCORRELATED TYPE II RADIO SWEEP OCCURRED AT 16/0744Z. THREE NEW REGIONS WERE NUMBERED TODAY AS REGION 8802 (S23E04), REGION 8803 (S14E24), AND REGION 8804 (S18E78).
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO REMAIN LOW. REGION 8798 IS CAPABLE OF PRODUCING AN ISOLATED M-CLASS EVENT.
IIA. Geophysical Activity Summary 15-2100Z to 16-2100Z
THE GEOMAGNETIC FIELD WAS QUIET THROUGH THE PERIOD.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS EXPECTED TO BE QUIET TO UNSETTLED FOR THE FORECAST PERIOD.
III. Event Probabilities 17 DEC to 19 DEC
Class M20%20%20%
Class X05%05%05%
Proton01%01%01%
PCAFGREEN
IV. Penticton 10.7 cm Flux
  Observed       16 DEC 194
  Predicted   17 DEC-19 DEC  200/210/195
  90 Day Mean        16 DEC 169
V. Geomagnetic A Indices
OBSERVED AFR/AP 15 DEC  002/004
ESTIMATED AFR/AP 16 DEC  005/005
PREDICTED AFR/AP 17 DEC-19 DEC  005/005-008/008-008/010
VI. Geomagnetic Activity Probabilities 17 DEC to 19 DEC
A. Middle Latitudes
Active10%10%10%
Minor storm05%05%05%
Major-severe storm01%01%01%
B. High Latitudes
Active10%10%15%
Minor storm05%05%10%
Major-severe storm01%01%05%

All times in UTC

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