Viewing archive of Friday, 20 December 2013

Solar activity report

Report of Solar-Geophysical Activity 2013 Dec 20 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 354 Issued at 2200Z on 20 Dec 2013

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

Solar activity has been at moderate levels for the past 24 hours. The largest solar event of the period was a M3 event observed at 19/2319Z from Region 1934 (S15E65). There are currently 9 numbered sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be low with a chance for M-class flares and a slight chance for an X-class flare on days one, two, and three (21 Dec, 22 Dec, 23 Dec).
IIA. Geophysical Activity Summary 19-2100Z to 20-2100Z
The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed, as measured by the ACE spacecraft, reached a peak speed of 391 km/s at 20/0820Z. Total IMF reached 5 nT at 20/0146Z. The maximum southward component of Bz reached -5 nT at 19/2201Z.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at quiet levels on days one, two, and three (21 Dec, 22 Dec, 23 Dec).
III. Event Probabilities 21 Dec to 23 Dec
Class M40%40%40%
Class X10%10%10%
IV. Penticton 10.7 cm Flux
  Observed       20 Dec 149
  Predicted   21 Dec-23 Dec 150/145/140
  90 Day Mean        20 Dec 140

V. Geomagnetic A Indices
  Observed Afr/Ap 19 Dec  004/004
  Estimated     Afr/Ap 20 Dec  006/006
  Predicted    Afr/Ap 21 Dec-23 Dec  005/005-005/005-005/005

VI. Geomagnetic Activity Probabilities 21 Dec to 23 Dec
A. Middle Latitudes
Minor storm01%01%01%
Major-severe storm01%01%01%
B. High Latitudes
Minor storm15%15%15%
Major-severe storm05%05%05%

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