Simulations of a North American Monsoon Gulf Surge Event

The North American Monsoon Experiment (NAME) produced a very extensive observational dataset of monsoon conditions throughout southwest Mexico and along the Gulf of California (GoC). The NAME captured two strong surge events in detail during July 2004. Recent work by Rogers and Johnson (2007) and others have examined the 12-14 July 2004 surge event using the NAME observational dataset. This work examines that same surge event through the use of the Weather Research and Forecasting Model (WRF) version 3.1. Several model runs ranging in horizontal resolution from 3.3-2 km were performed over a majority of the NAME domain for the 12-14 July 2004 surge event. Model comparisons to observations show the ability of the WRF model to reasonably simulate the surge event. The model reproduces the 12 July convection in similar locations, but 3-6 hours too early. The low level pressure and wind features at several sites along the GoC are quite similar to those observed, with somewhat weaker winds in the simulations. Some possible reasons for the discrepancies between the observations and simulations will be discussed along with further analysis of the evolution and dynamical characteristics of the surge event.