Viewing archive of Wednesday, 17 April 2013

Solar activity report

Report of Solar-Geophysical Activity 2013 Apr 17 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 107 Issued at 2200Z on 17 Apr 2013

IA. Analysis of Solar Active Regions and Activity from 16-2100Z to 17-2100Z

Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C3 event observed at 16/2132Z from Region 1719 (N09W64). There are currently 5 numbered sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is likely to be low with a slight chance for an M-class flare on days one and two (18 Apr, 19 Apr) and likely to be low on day three (20 Apr).
IIA. Geophysical Activity Summary 16-2100Z to 17-2100Z
The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed, as measured by the ACE spacecraft, reached a peak speed of 379 km/s at 17/0726Z.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at quiet levels on days one, two, and three (18 Apr, 19 Apr, 20 Apr).
III. Event Probabilities 18 Apr to 20 Apr
Class M10%10%05%
Class X01%01%01%
IV. Penticton 10.7 cm Flux
  Observed       17 Apr 108
  Predicted   18 Apr-20 Apr 100/100/095
  90 Day Mean        17 Apr 111

V. Geomagnetic A Indices
  Observed Afr/Ap 16 Apr  002/003
  Estimated     Afr/Ap 17 Apr  003/004
  Predicted    Afr/Ap 18 Apr-20 Apr  004/005-006/005-005/005

VI. Geomagnetic Activity Probabilities 18 Apr to 20 Apr
A. Middle Latitudes
Minor storm01%01%01%
Major-severe storm01%01%01%
B. High Latitudes
Minor storm15%15%15%
Major-severe storm10%10%10%

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