Rain and fog limited visibility in the area where a chopper crash-landed on a Midtown Manhattan building Monday, killing the pilot — though it wasn’t immediately clear what role, if any, the weather had in the accident.

At the time of the crash, both LaGuardia and Newark airports instituted ground-stops because of poor visibility and thunderstorms, according to the Federal Aviation Administration.

A ground stop is an air-traffic control measure that slows or halts the flow of planes into a given airport “when the projected traffic demand is expected to exceed the airport’s acceptance rate,” according to the FAA.

Hundreds of weather-related flight delays and cancellations also were reported across the Northeast on Monday.

Flights bound for JFK Airport also were delayed an average of 1 ½ hours due to the inclement weather, the FAA said.

With Post wires