I have no cold water upstairs. [Hot and Warm] I went down to kitchen and ran it. It went: cold - warm - and then cold again. The same thing happened in the downstairs bathroom and on the first floor laundry sink. The cold line in the garage is warm as well. The cold line on top of the gas water heater is warm, but where it tees off to the downstairs bathroom is cold. No leaks anywhere. The line into the house is cold.
It is 65 degrees outside and has been over 50 for four days. Not likely a frozen pipe. Or could this by the after effect of a frozen pipe that didn't burst, but merely thawed?
I hope I have given you enough to come up with a place for me to start.

