I've got a buddy in Tulsa that has some rental properties. Warned all the tenants to drip the faucets and all that, but still ended up with 4 frozen pipes, a busted hose bib (80 year old house and it wasn't frost-free), and a water heater. They get down to 0 from time to time and when I lived there even got down to -27 once, but it was always in short bursts (i was on my Sportster in 70 degrees two days after hitting -27). They're not used to days and days of prolonged sub-freezing temps. Even the natural gas company has lost 1/3 of their capacity because some of their giant pipeline valves are frozen shut due to normal water content in the gas.
On the other hand, we had a high of -2 and a low of -16 on Sunday and other than not having much desire to be outside, it didn't seem like a particularly abnormal winter day. It was even clear and sunny outside for most of the afternoon.
