What is a Ground Stop?
A ground stop is one of the most disruptive events in aviation. When one is issued, all flights headed to a specific airport are held at their departure airports until further notice. Here is what causes them and what they mean for your journey.
Quick Answer
A ground stop is an order issued by air traffic control that prevents aircraft from departing to a specific destination airport. Planes that are already in the air continue to their destination, but nothing new is allowed to take off until the ground stop is lifted.
Why Are Ground Stops Issued?
Severe weather
Thunderstorms, low visibility, heavy snow, or ice on the runway make it unsafe or impossible to land. This is the most common cause. A storm sitting directly over an airport can ground all inbound traffic for hours.
Airport capacity problems
If an airport is already overwhelmed with aircraft on the ground or circling overhead, a ground stop prevents the situation from getting worse. Runways have a fixed throughput - only so many planes can land per hour.
ATC system failures
If radar, communications, or flight management systems fail at a destination airport, controllers cannot safely manage arriving traffic. A ground stop buys time to restore systems or redirect flights.
Security incidents
A security threat, suspicious package, or emergency at an airport can trigger a ground stop while the situation is assessed and resolved.
Key Facts
30 min - 6 hrs
Typical Duration
Weather-related stops can extend longer
Local only
Scope
Affects one airport at a time in most cases
FAA / ATC
Issued By
Authority for destination airport
What Actually Happens to Your Flight
If your flight has not yet boarded, it will remain at the gate. The departure board will usually show a new estimated departure time, though this can change repeatedly as the ground stop is extended or lifted.
If your plane has already pushed back or is taxiing, the crew may be instructed to hold position on the taxiway. In longer ground stops, planes already in the departure queue are sometimes brought back to the gate to let passengers off and refuel.
If you have a connecting flight, a ground stop at your destination or your connecting airport will cascade. Airlines will typically rebook passengers on later flights, but seats are limited during major events.
US vs UK Ground Stops
UNITED STATES
Managed by the FAA through the Air Traffic Control System Command Center. Ground stops appear in the FAA NAS Status system, which AirStatus monitors directly. The FAA also issues Ground Delay Programs when a full stop is not needed - just a slowdown.
UNITED KINGDOM
Published via NATS NOTAMs and the PIB feed. UK ground stops are less formal in structure than FAA ones but have the same effect. NATS also coordinates with EUROCONTROL for pan-European flow restrictions.
What to Do
If your flight is caught in a ground stop
- ›Do not leave the gate area - ground stops can lift suddenly and boarding can start with very little notice.
- ›Check the airline app directly rather than departure boards, which can lag behind.
- ›If the delay looks like it will exceed 3 hours, start documenting it - keep your boarding pass and any messages from the airline.
- ›You are entitled to meals and refreshments under UK261/EU261 if the delay reaches 2 hours for short-haul flights.
- ›If your flight is cancelled because of the ground stop, you are entitled to a full refund or re-routing.
Airports Most Prone to Ground Stops
Not all airports are equally vulnerable. Geography, infrastructure, and traffic volume all determine how frequently a given airport suffers ground stops.
Chicago O'Hare (ORD) — Severe Midwestern thunderstorms
ORD sits in the path of frequent convective storm systems moving across the Great Plains. It is consistently one of the most delay-prone airports in the US, with ground stops occurring dozens of times per year. Its enormous size and complex taxiway layout mean that even a short ground stop causes a lengthy backlog.
San Francisco (SFO) — Marine layer fog
SFO is notorious for a thick marine layer fog that rolls in from the Pacific — sometimes burning off by midday, sometimes persisting all day. When visibility drops below instrument landing minimums, arrival rates are cut and ground stops follow. SFO has only two parallel runways, making it especially sensitive to any capacity reduction.
New York area (JFK / EWR / LGA) — Capacity and weather
The three New York area airports are among the busiest and most constrained in the world. They share the same airspace, compete for the same routes, and are frequently hit by Northeast weather systems. A ground stop at any one of them ripples across the other two almost immediately.
London Heathrow (LHR) — Capacity constraints
Heathrow operates two runways at near 100% utilisation. There is almost no spare capacity to absorb disruption. Any reduction in arrival rate — due to crosswinds, engineering works, or ATC restrictions — quickly results in ground stops or flow control restrictions across the whole of Europe, since LHR is a major hub for transatlantic connections.
How Long Do Ground Stops Actually Last?
Duration varies enormously depending on the cause. Weather-related stops tend to be unpredictable — they can lift in twenty minutes if a storm passes faster than forecast, or extend to six hours if a front stalls. ATC system failures can resolve quickly once engineers restore backup systems, but if the fault is severe, the stop may last the rest of the operating day.
The FAA and NATS issue regular updates — typically every 30 to 60 minutes — giving revised estimates of when the stop will be lifted. Airlines use these updates to decide whether to keep passengers at the gate or start rebooking passengers onto later flights.
THUNDERSTORM
30 min – 4 hrs
Improves as storm moves through
HEAVY SNOW / ICE
2 – 8 hrs
Depends on deicing capacity
ATC SYSTEM FAILURE
1 – 12 hrs
Depends on backup restoration