Viewing archive of Friday, 13 August 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 Aug 13 2200 UTC
Prepared by the NOAA © SWPC and processed by SpaceWeatherLive.com

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 225 Issued at 2200Z on 13 AUG 1999

IA. Analysis of Solar Active Regions and Activity from 12-2100Z to 13-2100Z

SOLAR ACTIVITY WAS LOW. REGION 8662 (S16W33) PRODUCED SEVERAL C-CLASS FLARES, THE LARGEST OF WHICH WAS A C4/SF AT 13/1559UT. DECAY, PARTICULARLY IN THE TRAILER SUNSPOTS, IS CONTINUING. NEW REGION 8668 (N21E75) IS ROTATING AROUND THE EAST LIMB.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE LOW TO MODERATE. C-CLASS FLARES ARE EXPECTED IN REGION 8662. A LOW-LEVEL M-CLASS FLARE IS ALSO POSSIBLE IN THIS REGION.
IIA. Geophysical Activity Summary 12-2100Z to 13-2100Z
THE GEOMAGNETIC FIELD RANGED FROM QUIET TO ACTIVE. A SINGLE ACTIVE PERIOD OCCURRED FROM 13/0300-0600UT.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS EXPECTED TO BE QUIET TO UNSETTLED.
III. Event Probabilities 14 AUG to 16 AUG
Class M10%10%10%
Class X01%01%01%
Proton01%01%01%
PCAFGREEN
IV. Penticton 10.7 cm Flux
  Observed       13 AUG 127
  Predicted   14 AUG-16 AUG  128/130/132
  90 Day Mean        13 AUG 163
V. Geomagnetic A Indices
OBSERVED AFR/AP 12 AUG  008/010
ESTIMATED AFR/AP 13 AUG  010/010
PREDICTED AFR/AP 14 AUG-16 AUG  010/010-010/008-010/008
VI. Geomagnetic Activity Probabilities 14 AUG to 16 AUG
A. Middle Latitudes
Active15%15%15%
Minor storm01%01%01%
Major-severe storm01%01%01%
B. High Latitudes
Active15%15%15%
Minor storm05%05%05%
Major-severe storm01%01%01%

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