How long can a cat go without food or water?

I trapped a cat on Sunday night and kept the trap and cat in my storage shed overnight. In the morning it was raining and cold, so I didn't want to throw the whole thing in the back of the truck to go to the vet's. In transferring the cat to a carrier, I almost had the carrier door closed when the cat escaped, into my shed.

The cat bounced around the shelves and under the wood scraps for a few minutes until it found a good hiding place. I had to go to work so I closed the door and locked it in.

I set the trap and put food in it. Tonight I replaced the food with fresh wet.

How long until this feral cat is hungry enough to go into the trap again?

Mary