Viewing archive of Sunday, 10 April 2011

Solar activity report

Report of Solar-Geophysical Activity 2011 Apr 10 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 100 Issued at 2200Z on 10 Apr 2011

IA. Analysis of Solar Active Regions and Activity from 09-2100Z to 10-2100Z

Solar activity was very low. Only B-class events were observed. Region 1185 (N18E01) grew from an area of 30 millionths to 60 millionths. Region 1186 (N23E06) grew from 40 millionths to 70 millionths. Regions 1188 (S24W34) and 1189 (N23W16) are now plage regions. A CME was observed on SOHO/LASCO C2 imagery on the Northeast limb at approximately 10/0312Z.
IB. Solar Activity Forecast
Solar activity is expected to be very low to low with a slight chance for C-class flares for the next three days (11 - 13 April).
IIA. Geophysical Activity Summary 09-2100Z to 10-2100Z
The geomagnetic field was at quiet levels.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at quiet to unsettled levels, with isolated active levels at mid-latitudes on day one (11 April). The increase in activity is due to a coronal hole high-speed stream. Activity is expected to decrease to mostly quiet levels on days two and three (12 - 13 April) as the coronal hole high-speed stream effects wane. The CME referenced in paragraph 1A, is not expected to be geoeffective.
III. Event Probabilities 11 Apr to 13 Apr
Class M01%01%01%
Class X01%01%01%
IV. Penticton 10.7 cm Flux
  Observed       10 Apr 105
  Predicted   11 Apr-13 Apr  095/100/100
  90 Day Mean        10 Apr 101
V. Geomagnetic A Indices
  Observed Afr/Ap 09 Apr  004/010
  Estimated     Afr/Ap 10 Apr  005/005
  Predicted    Afr/Ap 11 Apr-13 Apr  010/012-005/005-005/005
VI. Geomagnetic Activity Probabilities 11 Apr to 13 Apr
A. Middle Latitudes
Minor storm05%01%01%
Major-severe storm01%01%01%
B. High Latitudes
Minor storm10%01%01%
Major-severe storm05%01%01%

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