August 2003, such an event occurred in Las Vegas, Nevada where some areas received over of rain in half an hour. Summarizing the work of Hales and Brenner, Fuller and Stensrud describe the effects that are commonly associated with gulf surges. During the onset of the surge, surface temperatures will drop, the dew point will rise, and sea level pressure will decrease. Winds will swing from northwesterly to southerly. These changes produce lower visibility and low clouds. This results in increased low-level cooling that is greatest at the surface and decreases with height. As the surge reaches the northern tip of the gulf, the surge spreads into the southern Arizona valley and the cooling diffuses. The increased water vapor results in an increase in the number of thunderstorms in Arizona. See also Continental Divide of the Americas Convective instability Peninsular Ranges References Climate of the United States Climate of Mexico Gulf of California Mexican Plateau