Calling all atmospheric sciences geeks: the National Weather Service recently moved in to fancy new headquarters in Sterling, Va., and they’re throwing an open house this weekend that’s open to the public. Potentially awesome weather stuff you’ll get to check out, if you go: >> Free basic “weather spotter” classes (?) >> Weather balloon launches every hour (!) >> Tours of NOAA’s wind tunnel & environmental extreme chambers (!!) Less potentially awesome: >> “Weather in…