Viewing archive of Sunday, 28 August 2011

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 2011 Aug 28 2200 UTC
Prepared by the NOAA © SWPC and processed by SpaceWeatherLive.com

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 240 Issued at 2200Z on 28 Aug 2011

IA. Analysis of Solar Active Regions and Activity from 27-2100Z to 28-2100Z

Solar activity was very low. New Region 1281 (S21E64) produced occasional optical subflares during the period, two of which were associated with B-class x-ray flares. No significant activity was noted in the remaining spot groups. A weak Type II radio sweep occurred at 28/0420Z, likely associated with a filament disappearance from beyond the west limb. There were no Earth-directed CMEs observed during the period.
IB. Solar Activity Forecast
Solar activity is expected to be very low during the period (29 - 31 August) with a chance for an isolated C-class flare.
IIA. Geophysical Activity Summary 27-2100Z to 28-2100Z
The geomagnetic field was quiet.
IIB. Geophysical Activity Forecast
Geomagnetic field activity is expected to be at quiet to unsettled levels on day 1 (29 August). Quiet geomagnetic conditions are expected during days 2 - 3 (30 - 31 August).
III. Event Probabilities 29 Aug to 31 Aug
Class M01%01%01%
Class X01%01%01%
Proton01%01%01%
PCAFGreen
IV. Penticton 10.7 cm Flux
  Observed       28 Aug 101
  Predicted   29 Aug-31 Aug  100/098/095
  90 Day Mean        28 Aug 097
V. Geomagnetic A Indices
  Observed Afr/Ap 27 Aug  003/005
  Estimated     Afr/Ap 28 Aug  005/008
  Predicted    Afr/Ap 29 Aug-31 Aug  008/008-005/005-005/005
VI. Geomagnetic Activity Probabilities 29 Aug to 31 Aug
A. Middle Latitudes
Active20%15%15%
Minor storm05%01%01%
Major-severe storm01%01%01%
B. High Latitudes
Active25%20%15%
Minor storm10%05%01%
Major-severe storm01%01%01%

All times in UTC

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