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The NCEP/NCAR reanalysis data (1°×1°，6 h) in January 2011 and the observation data in winter from 1970 to 2011 provided by Guizhou Meteorological Service are used to investigate the climatic characteristics of freezing disaster occurred in January 2011 and its causes by climate statistics and climate diagnostic methods. More than 34 stations reached the lowest temperature in the past 40 years during the freezing rain event. There were active blocking anticyclones near the Ural Mountains persistently, which were more active than the normal. They were broken down twice and rebuilt thrice, with the wet southwesterly flow brought by the strong Caspian Sea trough, supplying the warm air constantly. There was a strong and steady high existed in the front of the Urals blocking high and the frequent activities of trough, bringing cold air to the western China, which resulted in the freezing disaster in Guizhou region.