Assessing the Ability of WRF to Simulate Wintertime Near-Surface Icing Conditions over the Southwestern United States

It is important to consider the hazards associated with icing on aircraft and ground structures when examining structural design, risk mitigation and operations. Defined as any amount of ice accumulation or snow accretion on the surface of an object exposed to the atmosphere, icing may be produced by cloud droplets, raindrops, wet snow, or water vapor. In general, icing that causes significant aerodynamic effects or loading problems occurs when super-cooled liquid water droplets collide with subfreezing structures.  Several algorithms have been developed to describe ice accretion, but they are dependent upon reliable observations of the meteorological conditions at the particular site of interest.

This study investigates the potential for accurately simulating near-surface icing conditions using the Weather Research and Forecasting (WRF) model. Model performance with regards to explicit simulation of super-cooled cloud liquid water content, cloud droplet diameter, temperature, and wind speed is evaluated against observations near two distinct summits in Arizona. Results from the case studies analysis will be compared with previous study results examining icing conditions other locations with a goal of providing guidance for model configuration for icing purposes.