I massive irregular operations event related to a snowstorm, the storm can be gone but sometimes it takes a few days to get things back on schedule due to aircraft and crew positioning to be able to operate. It depends on the airline and type of operation. For example if you were flying CO at EWR you may have a better chance of having flights operate after a storm as they have alot of aircraft and crews based there. This is also why airlines pre-cancel before the storm which seems to help return operations back to normal in a more timly manner.