Orographic Precipitation Enhancement Over the Olympic Peninsula

The Olympic Mountains Experiment (OLYMPEX) was a ground validation field campaign centered around the Olympic Peninsula designed to provide physical validation and verification of satellite precipitation measurements from the constellation of satellites known as the Global Precipitation Measurement (GPM). The goal of OLYMPEX was to validate and document precipitation measurements in midlatitude frontal systems moving from the Pacific Ocean to the coast and then to the high terrain and leeside. The assets featured in OLYMPEX included extensive ground instrumentation, soundings and dropsondes, several radars, and aircraft all helping to monitoring storm systems as they approached and then traversed the Olympic Peninsula during the intensive field operations from November 2015 through March 2016. Specifically, ground instrumentation was located at a number of different elevations mainly focusing on the windward southwest side of the Olympic Mountains and scattered in other areas of the Olympic Peninsula in locations where precipitation has not been previously measured. This presentation will look at patterns of orographic precipitation enhancement using this extensive gauge network to describe and quantify patterns of enhancement and how they vary with synoptic conditions. The key synoptic parameters that may affect the patterns of enhancement include the stability, the strength and direction of the low level flow, the intensity of synoptic scale forcing and the transport of water vapor.  These parameters can vary with storm intensity and storm sector.