CW3E AR Update: 9-13 December 2016 Outlook

December 9, 2016

Click here for a pdf of this information.

Landfalling AR to impact California

  • A moderate AR is expected to make landfall in north/central California tonight
  • The AR propagates southward over the weekend bringing AR conditions to portions of southern California
  • Current precipitation forecast suggests higher precipitation amounts of up to 150 mm over the Sierra Nevada Mts., while the Coastal Mts. are not expected to receive as much
  • Above normal soil moisture conditions in northwestern CA suggest that conditions are primed for more of the precipitation to turn into runoff rather than be lost to moistening the soil
  • Extended forecasts suggest the landfall of another AR over southern California on the 13th, but forecast confidence is currently low

GFS forecast from 06 UTC 9 Dec – 00 UTC 13 Dec 2016, showing IVT (shading and vectors) and sea level pressure





Summary provided by C. Hecht, and F.M. Ralph; 3 PM PT Fri 09 Dec. 2016