It got pretty cold here last night and I woke up to very low water pressure this morning. My house is off a well system. Went down to the basement and no leaks and no burst pipes.
The other day with the low temps and wind. They live in an old colonial, where some of the pipes run it is very drafty. They were starting to get a icy/slushy. Just had to open a few closets where the pipes run to get some heat through better, hope it’s a quick fix.
It may be the tank off your well. It may not be holding pressure. If you gently slap the tank and it sounds like its full the diaphragm/bladder in the tank may be shot. Sounds similar to something that happened to me a few years back.
That it occurred during extreme cold I would wait for things to warm up as it may be partially frozen pipes. Until then I recommend letting a number of faucets drip.
There are a number of potential causes. But given it happened in combination with the cold, freezing pipes would be the most likely. As advised above, open closet/cabinet doors where pipes are behind to allow heat to access walls with pipes and let an upstairs faucet drip.
Once things warm up sufficiently you can move on to other causes if it doesn’t resolve.
If it is a frozen pipe situation: If not all faucet you can narrow down the problem area. Then look at the pipes in that area and look for pipes close to the wall or poor insulated areas. Use a hair dryer on the pipe. Oh, also is it just the cold or both hot and cold. If it's both, the hot should clear pretty quickly with running water, but the cold may take a while. If hot water running doesn't clear the hot water line then its probably something else.
Have a pressure gauge on the line into the house?
It may be the tank off your well. It may not be holding pressure. If you gently slap the tank and it sounds like its full the diaphragm/bladder in the tank may be shot. Sounds similar to something that happened to me a few years back.
Once things warm up sufficiently you can move on to other causes if it doesn’t resolve.
My 30/50 pressure gauge is staying at 30 unless I manually force it to go to 50.
Update. This was the answer. I tried all the answers in here and a clogged filter was restricting the water flow. Thanks to all those who helped out!