More than a hundred tornadoes are expected for nearly the half the nation, with the National Weather Service's Storm Prediction Center projecting the likelihood of funnel clouds developing into potentially deadly tornadoes to increase with each passing hour.
Residents of Arkansas and Missouri have the greatest tornado risk, but virtually the entire South and most of the Midwest must brace for some form of severe weather. Forecasters also predict baseball-sized hail and winds up to 75 mph.
Severe thunderstorms have already forced organizers to delay the Oklahoma City Memorial Marathon, a race held to commemorate victims of the 1995 domestic terrorist attack. The weather pattern is currently expected to last throughout the week, potentially clearing up Friday or Saturday.
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