Cold weather here connected to tornadoes there

(05-25) 17:33 PDT SAN FRANCISCO -- That unseasonably cool air blowing through the Bay Area this week was one of the ingredients that created deadly tornado outbreaks in the Midwest, according to weather experts.
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Jan Null, a meteorologist who runs Golden Gate Weather Services, said, "This isn't global warming, this isn't climate change. This all falls under the category of, 'Stuff happens.' "