Viewing archive of Tuesday, 27 September 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 Sep 27 2210 UTC
Prepared by the NOAA © SWPC and processed by SpaceWeatherLive.com

Joint USAF/NOAA Report of Solar and Geophysical Activity

:::::::::: CORRECTED COPY :::::::::: SDF Number 270 Issued at 2200Z on 27 Sep 2011

IA. Analysis of Solar Active Regions and Activity from 26-2100Z to 27-2100Z

Solar activity was low. Several C-class flares occurred during the period from Region 1302 (N13E08). The largest of these was a C6 flare at 27/2058Z.
IB. Solar Activity Forecast
Solar activity is expected to be low, with a chance for M-class during the period (28-30 September). There will also be a chance for an X-class flare.
IIA. Geophysical Activity Summary 26-2100Z to 27-2100Z
The geomagnetic field ranged from quiet to active levels. An isolated period of major to severe storm levels were observed from 27/0000-0300Z. The greater than 10 MeV proton event began at 23/2255Z, reached a maximum of 35.7 pfu at 26/1155Z, and ended at 27/0430Z. Wind speeds reached 704 km/s at 26/2150Z and decreased to 512 km/s at 27/1703Z.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at quiet to unsettled levels on day one (28 September). Quiet levels are expected on days two and three (29-30 September).
III. Event Probabilities 28 Sep to 30 Sep
Class M40%40%40%
Class X25%25%25%
Proton10%10%10%
PCAFgreen
IV. Penticton 10.7 cm Flux
  Observed       27 Sep 139
  Predicted   28 Sep-30 Sep  135/135/130
  90 Day Mean        27 Sep 109
V. Geomagnetic A Indices
  Observed Afr/Ap 26 Sep  020/067
  Estimated     Afr/Ap 27 Sep  020/040
  Predicted    Afr/Ap 28 Sep-30 Sep  008/015-005/005-005/005
VI. Geomagnetic Activity Probabilities 28 Sep to 30 Sep
A. Middle Latitudes
Active15%05%05%
Minor storm01%01%01%
Major-severe storm01%01%01%
B. High Latitudes
Active20%05%05%
Minor storm05%01%01%
Major-severe storm01%01%01%

All times in UTC

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