Viewing archive of Tuesday, 26 October 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 Oct 26 2200 UTC
Prepared by the NOAA © SWPC and processed by SpaceWeatherLive.com

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 299 Issued at 2200Z on 26 OCT 1999

IA. Analysis of Solar Active Regions and Activity from 25-2100Z to 26-2100Z

SOLAR ACTIVITY WAS MODERATE. REGION 8739 (S11W10) PRODUCED THE LARGEST FLARE OF THE PAST DAY, AN M2/1N AT 26/1852UT. THIS REGION CONTINUES TO DEVELOP AND NOW HAS AN OVERALL SUNSPOT AREA OF ABOUT 800+ MILLIONTHS, INCLUDING MIXED POLARITIES AND A MAGNETIC DELTA CONFIGURATION. REGION 8739 ALSO GENERATED SEVERAL C-CLASS FLARES. REGIONS 8737 (S15W78) AND 8741 (S25E09) ALSO PRODUCED C-CLASS ACTIVITY. NEW REGION 8745 (S14E66) IS ROTATING AROUND THE EAST LIMB.
IB. Solar Activity Forecast
SOLAR ACTIVITY IS EXPECTED TO BE LOW TO MODERATE. C-CLASS ACTIVITY IS EXPECTED FROM REGIONS 8737, 8739, AND 8741. A MAJOR FLARE IN REGION 8739 IS POSSIBLE.
IIA. Geophysical Activity Summary 25-2100Z to 26-2100Z
THE GEOMAGNETIC FIELD WAS QUIET TO UNSETTLED. THE GREATER THAN 2 MEV ELECTRON FLUX AT GEOSYNCHRONOUS ORBIT WAS HIGH.
IIB. Geophysical Activity Forecast
THE GEOMAGNETIC FIELD IS EXPECTED TO BE QUIET TO UNSETTLED. ACTIVITY LEVELS MAY BE INFLUENCED BY A HIGH-SPEED CORONAL HOLE STREAM TOWARDS THE END OF THE FORECAST PERIOD.
III. Event Probabilities 27 OCT to 29 OCT
Class M60%60%60%
Class X05%05%05%
Proton05%05%05%
PCAFGREEN
IV. Penticton 10.7 cm Flux
  Observed       26 OCT 189
  Predicted   27 OCT-29 OCT  190/190/185
  90 Day Mean        26 OCT 158
V. Geomagnetic A Indices
OBSERVED AFR/AP 25 OCT  010/018
ESTIMATED AFR/AP 26 OCT  012/012
PREDICTED AFR/AP 27 OCT-29 OCT  010/015-015/015-015/025
VI. Geomagnetic Activity Probabilities 27 OCT to 29 OCT
A. Middle Latitudes
Active15%15%15%
Minor storm05%05%05%
Major-severe storm02%02%02%
B. High Latitudes
Active15%15%15%
Minor storm05%05%05%
Major-severe storm02%02%02%

All times in UTC

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