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On June 4, 2013, the city of Huntsville, Alabama was enjoying a gorgeous day. Blue skies, mild temperatures. Just what the forecasters had predicted.
But in the post-lunch hours, meteorologists started picking up what seemed to be a rogue thunderstorm on the weather radar. The “blob,” as they referred to it, mushroomed on the radar screen. By 4 PM, it covered the entire city of Huntsville. Strangely, however, the actual view out of peoples’ windows remained a calm azure.