Viewing archive of Friday, 21 January 2011

Solar activity report

Report of Solar-Geophysical Activity 2011 Jan 21 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 021 Issued at 2200Z on 21 Jan 2011

IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z

Solar activity was low. Region 1147 (N24W07) and new Region 1149 (N18W05) produced several C-class flares during the period. Region 1149 produced a C3 flare at 21/0417Z. This was the largest flare observed during the past 24 hours.
IB. Solar Activity Forecast
Solar activity is expected to be low with a slight chance for an isolated M-class flare from Region 1149.
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
The geomagnetic field was quiet.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be quiet to unsettled on day one (22 January), due to a coronal hole high-speed stream (CH HSS). Activity should decrease to quiet levels on days two and three (23 - 24 January) as the effects of the CH HSS wane.
III. Event Probabilities 22 Jan to 24 Jan
Class M10%10%10%
Class X01%01%01%
IV. Penticton 10.7 cm Flux
  Observed       21 Jan 088
  Predicted   22 Jan-24 Jan  085/085/085
  90 Day Mean        21 Jan 084
V. Geomagnetic A Indices
  Observed Afr/Ap 20 Jan  004/003
  Estimated     Afr/Ap 21 Jan  005/005
  Predicted    Afr/Ap 22 Jan-24 Jan  007/007-005/005-005/005
VI. Geomagnetic Activity Probabilities 22 Jan to 24 Jan
A. Middle Latitudes
Minor storm01%01%01%
Major-severe storm01%01%01%
B. High Latitudes
Minor storm05%01%01%
Major-severe storm01%01%01%

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