Viewing archive of Monday, 16 May 2011

Solar activity report

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

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 136 Issued at 2200Z on 16 May 2011

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

Solar activity was low during the past 24 hours. Region 1208 (N08W64) produced a C4 event at 15/2334Z. An associated CME was first observed on LASCO C2 imagery at 16/0024Z and had an estimated plane-of-sky speed of 250 km/s. It is not expected to be geoeffective. New Region 1216 (S14E66) was numbered today and is considered an Hsx group at this time.
IB. Solar Activity Forecast
Solar activity is expected to remain low for the next three days (17-19 May).
IIA. Geophysical Activity Summary 15-2100Z to 16-2100Z
The geomagnetic field was quiet to unsettled with an isolated active period at 15/1800Z due the effects of a recurrent coronal hole high speed stream (CH HSS).
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be quiet to unsettled with a chance for isolated active periods for day one (17 May). A decline from quiet to unsettled to mostly quiet conditions is expected on days two and three (18-19 May) as the CH HSS gradually subsides.
III. Event Probabilities 17 May to 19 May
Class M 05%05%05%
Class X 01%01%01%
IV. Penticton 10.7 cm Flux
  Observed       16 May 092
  Predicted    17 May-19 May  090/090/095
  90 Day Mean        16 May 109
V. Geomagnetic A Indices
  Observed Afr/Ap 15 May  009/011
  Estimated     Afr/Ap 16 May  010/012
  Predicted     Afr/Ap 17 May-19 May  008/010-005/005-005/005
VI. Geomagnetic Activity Probabilities 17 May to 19 May
A. Middle Latitudes
Minor storm 05%01%01%
Major-severe storm 01%01%01%
B. High Latitudes
Minor storm 05%01%01%
Major-severe storm 01%01%01%

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