Today is the second day of a two-part severe weather outbreak across the Plains states, with giant thunderstorms blowing up over Oklahoma and Arkansas. The storms have the potential to produce hail up to the size of tennis balls, so naturally, storm chasers are speeding towards them in hopes of catching nature at its fiercest.

The program I used here, GREarth, allows you to overlay dozens of variables on a map, including the location of storm spotters who are relaying their positions via GPS devices. The multicolored car dots shows each storm chasing vehicle, while the yellow boxes show severe thunderstorm warnings issued for each storm as it starts to produce large hail.

It's pretty mesmerizing to watch the chasers race towards storms once they bubbled up west of Tulsa.

A moderate risk for severe weather—a four on a scale from zero to five—is in place across the parts of Oklahoma and Arkansas seeing storms right now. Just like yesterday, most of today's storms are prolific hail producers, with at least nine reports of hail the size of golf balls or larger as of 5:00 PM CDT.

As the evening progresses, the storms should start to merge into squall lines as they move east towards the Mississippi and Ohio River Valleys. The threat for severe weather shifts east tomorrow, with a marginal risk for some damaging winds across coastal parts of Virginia, Maryland, and North Carolina.

[Image: GREarth]

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