If you turn on a faucet and only a trickle comes out, suspect a frozen pipe. Likely places for frozen pipes include against exterior walls or where your water service enters your home through the foundation.
Keep the faucet open. As you treat the frozen pipe and the frozen area begins to melt, water will begin to flow through the frozen area. Running water through the pipe will help melt ice in the pipe.
Apply heat to the section of pipe using an electric heating pad wrapped around the pipe, an electric hair dryer, a portable space heater (kept away from flammable materials), or by wrapping pipes with towels soaked in hot water. Do not use a blowtorch, kerosene or propane heater, charcoal stove, or other open flame device.
Apply heat until full water pressure is restored. If you are unable to locate the frozen area, if the frozen area is not accessible, or if you can not thaw the pipe, call a licensed plumber.
Check all other faucets in your home to find out if you have additional frozen pipes. If one pipe freezes, others may freeze, too.