Castro says the pipes most likely to freeze are those running along an exterior wall, or near a window. In cold weather, water meters can freeze, too.
The American Red Cross suggests taking preventative steps, such as keeping garage doors closed if there are water supply lines there, opening kitchen and bathroom doors to allow heat to circulate around the plumbing, and letting cold water drip from faucets served by exposed pipes.
If you need to thaw pipes, the Red Cross suggests wrapping them with an electric heating pad, or apply heat using a hair dryer or portable space heater - so long as its kept away from flammable material. Never use an open flame to attempt to thaw frozen water pipes.