In the last issue, we discussed cold weather systems that affect the United States and how they originate from the West Coast, especially during El Niño years, when there is a stronger west-to-east progression of systems across the country. Once they cross the Rocky Mountains, they normally appear in Texas, Oklahoma, or Kansas, and this is the point at which forecasts for places like Dallas, Texas; Chicago, Illinois; New York City, New York; and Memphis, Tennessee, can range anywhere from winter weather to severe storms and heavy rain. Even the famous 1975 storm that sank the S.S. Edmund Fitzgerald in Lake Superior got its start a day earlier as a low pressure system in Kansas.
TIM VASQUEZ is a former Air Force forecaster and author of Digital Atmosphere, a weather forecasting software program. He lives near Norman, Oklahoma, where he keeps busy as a weather consultant and software developer.