Viewing archive of Saturday, 16 April 2011

Solar activity report

Report of Solar-Geophysical Activity 2011 Apr 16 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 106 Issued at 2200Z on 16 Apr 2011

IA. Analysis of Solar Active Regions and Activity from 15-2100Z to 16-2100Z

Solar activity was at low levels. Occasional C-class flares were observed during the period. Two C5 flares were observed from Region 1190 (N14W40): a C5/Sf flare at 16/0057Z and a C5/Sf flare at 16/1414Z. Additionally, Region 1185 (N14W93) produced a C3 flare at 16/1653Z Regions 1190 and 1193 continue to remain the most significant regions on the disk. The CME mentioned in the forecast yesterday is not expected to disturb the field during the forecast period (17-19 April).
IB. Solar Activity Forecast
Solar activity is expected to be at low levels, with C-class flares expected for the next three days (17-19 April). There is also a chance for M-class flares during the period.
IIA. Geophysical Activity Summary 15-2100Z to 16-2100Z
The geomagnetic field was at quiet levels. The greater than 2 MeV electron flux at geosynchronous orbit reached high levels during the period.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at predominantly quiet levels for the next three days (17-19 April).
III. Event Probabilities 17 Apr to 19 Apr
Class M 40%40%40%
Class X 05%05%05%
IV. Penticton 10.7 cm Flux
  Observed       16 Apr 119
  Predicted    17 Apr-19 Apr  123/125/128
  90 Day Mean        16 Apr 103
V. Geomagnetic A Indices
  Observed Afr/Ap 15 Apr  003/006
  Estimated     Afr/Ap 16 Apr  002/005
  Predicted     Afr/Ap 17 Apr-19 Apr  005/005-005/005-005/005
VI. Geomagnetic Activity Probabilities 17 Apr to 19 Apr
A. Middle Latitudes
Minor storm 01%01%01%
Major-severe storm 01%01%01%
B. High Latitudes
Minor storm 01%01%01%
Major-severe storm 01%01%01%

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