If the water pipes are exposed to the cold air and wind then the water pipes can freeze once the temperature reaches 32 F or below.
If the water pipes are protected from the cold and wind then it may take as cold as 25 F to cause the water pipes to freeze.
But even if your house is only 30 F or so the water pipes in the house can freeze.
So make sure you keep your indoor heat temperature at warm enough temperature to keep the pipes from freezing, bursting and causing flood damage and plumbing issues.
I would keep the indoor temperature at least 50 F or above to keep the water pipes from freezing.
Wrap any exposed pipes in pipe insulation and if the pipes are outside use a water pipe heat tape that comes on automatically at a set temperature to keep the water pipes from freezing.
Also allow the water in the faucets to drip some and run at a slow steady stream to keep the pipes from freezing if the temperature outside gets really cold.