In Illinois, temperatures could rise by 80 degrees within days. In Michigan, melting snow and rain and a 17-mile ice jam could lead to flooding. Across the Midwest, the sudden warmth was sure to bring more broken roads and busted water mains, per the AP. The polar vortex that brought many cities to a standstill was expected to end with a rapid thaw that experts say could be unprecedented. But the sudden swing from long johns to light jackets and short sleeves could create problems of its own. "I don't think there's ever been a case where we've seen (such a big) shift in temperatures," in the winter, said Jeff Masters, meteorology director of the Weather Underground firm. "Past record-cold waves have not dissipated this quickly. ... Here we are going right into spring-like temperatures."
On Thursday, the system marched east, spreading arctic conditions over an area from Buffalo to Brooklyn. In western New York, for example, a storm that dumped up to 20 inches of snow gave way to subzero temperatures and face-stinging wind chills. The number of deaths that could be blamed on the cold climbed to at least 15. For the nation's midsection, however, relief was as close as the weekend. Rockford, Illinois, was at a record-breaking minus 31 on Thursday morning but should be around 50 on Monday. Other previously frozen areas could see temperatures of 55 or higher. Still, the thawing of pipes can sometimes inflict greater damage than the initial freeze. Bursts can occur when ice inside starts to melt and water rushes through the pipe, or when water in the pipe is pushed to a closed faucet by expanding ice.
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