Viewing archive of Tuesday, 20 September 2011

Solar activity report

Report of Solar-Geophysical Activity 2011 Sep 20 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 263 Issued at 2200Z on 20 Sep 2011

IA. Analysis of Solar Active Regions and Activity from 19-2100Z to 20-2100Z

Solar activity was low. A spot group complex consisting of Regions 1295 (N23W35), 1296 (N27W16) and 1298 (N15W36) produced several C-class events in the past 24 hours, including a C9/1f flare at 20/0513Z. SOHO LASCO imagery observed 4 CMEs again this period, none of which are expected to be geoeffective. Region 1295 remains a beta gamma magnetic configuration.
IB. Solar Activity Forecast
Solar activity is expected to be low for the next three days (21-23 September). A chance for isolated M-class flares exists from the Region 1295 complex.
IIA. Geophysical Activity Summary 19-2100Z to 20-2100Z
The geomagnetic field was mostly quiet with an isolated active period from 20/0300-0600Z.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be quiet to unsettled for the next three days (21-23 September).
III. Event Probabilities 21 Sep to 23 Sep
Class M40%40%40%
Class X01%01%01%
IV. Penticton 10.7 cm Flux
  Observed       20 Sep 144
  Predicted   21 Sep-23 Sep  145/145/145
  90 Day Mean        20 Sep 104
V. Geomagnetic A Indices
  Observed Afr/Ap 19 Sep  002/003
  Estimated     Afr/Ap 20 Sep  006/006
  Predicted    Afr/Ap 21 Sep-23 Sep  005/005-005/005-005/005
VI. Geomagnetic Activity Probabilities 21 Sep to 23 Sep
A. Middle Latitudes
Minor storm01%01%01%
Major-severe storm01%01%01%
B. High Latitudes
Minor storm01%01%01%
Major-severe storm01%01%01%

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