Posted 9:19 PM 1/13/2012 : Dry December has half of CA listed in 'drought' by U.S. Drought Monitor
Last year and this year are both La Nina years, where the ocean waters are cooler than normal near the equator which impacts the flow of weather systems. Last year was an abnormally wet La Nina for California (not all La Ninas are dry or El Ninos wet, it is often over simplified).
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