WRF Cold-Pool Sensitivities Relevant to Winter Ozone Modelling in the Uinta Basin

Cold-pool structure controls the confinement of wintertime ozone and its precursors in Utah’s Uinta Basin. Previous studies have documented difficulty capturing stable cold pools in meteorological models, complicating air quality simulations when pollutants disperse too readily. Herein, we evaluate the meteorology behind one such high-ozone event on 2 February 2013 with Weather Research and Forecasting (WRF) simulations; the chemistry is not simulated. We test the sensitivity to Global Forecast System (GFS) or North American Mesoscale (NAM) forcing, domain feedback, boundary-layer and surface-layer schemes, slope-aware radiation, and terrain datasets (fine versus coarse). Across five hourly samples, GFS-driven runs were warmer at the evaluated surface sites, had an approximately 3.6 K smaller 50–500 m potential-temperature endpoint difference, and had a 0.8–1.0 m s−1 larger layer-mean wind-vector magnitude than feedback-matched NAM runs. The GFS also retained a lower mean heat deficit, indicating a weaker modelled cold pool. The heat deficit increased in all four runs from 1400 to 1800 UTC; hence the difference in driving model suggests a state difference without demonstrated faster cold-pool erosion. Toggling feedback and parametrisation settings yielded smaller responses; terrain fineness produced spatial responses that station comparisons could miss. The results guide diagnostics for subsequent air-chemistry modelling, while leaving initial versus lateral forcing, cold-pool depth, and basin export for future studies.