The other wasn't just about cold air, either. In both cases there had been a lot of rain recently and they were concerned about black ice. My daughter was out of school this last time and I had no reason to go out, but during the previous delays I went out about 11:00am and there was still ice on the roads at that time, so it would have been more dangerous before the sun came up when the black ice is harder to see. They did it to keep the kids safe.
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