The Utility of Convection-allowing Ensemble Forecasts of Cool Season Severe Weather Events from the SPC Perspective

The majority of recent peer-reviewed and conference examinations of deterministic convection-allowing models (CAMs) and convection-allowing ensemble forecasts have focused on warm season severe weather events and tornado outbreaks. Even in lower instability regimes as more typical of cool season environments, forecasters at the Storm Prediction Center (SPC) have found convection-allowing ensemble forecast hourly maximum fields (HMFs) to be helpful in forecasting the intensity, spatial locations, and convective modes of severe convective storms. In particular, HMFs of simulated reflectivity, updraft helicity, updraft speed, and 10-m wind speed have been noted to exhibit forecast utility. Convection-allowing ensemble forecast output guidance including the SPC Storm-Scale Ensemble of Opportunity (SSEO) and the Air Force Weather Agency (AFWA) 4-km Ensemble Prediction System will be highlighted in an aggregate examination of recent cool season regional severe weather outbreaks that include 17 November 2013, 31 October 2013, 29 January 2013, and 25 December 2012.