Some animals are like humans. There are a few nuts that will venture out but most will hold up till it warms up a bit.
Also how many did you catch in the area? You might have to move on to another spot cause you caught them all in that place. Another wise decision to do is try not to catch all the fox out of an area . Take like 3 or 4 and don't target them any more. Need to repopulate the area and if you catch them all,it will be a while before any more move into that area. I will say bad weather or you caught them all. Let the traps be for a few days and see what happens. If anything get in and lure them real quick and get out. If nothing after a few days. Pull your traps and move to another location. Coons can be caught when real cold,but you have to be close to where they den. They don't venture far if they do come out in the cold.