How turbulent is LHR-EWR typically?

Typically light chop with occasional moderate patches where the track crosses the polar jet stream. Winter flights are bumpier than summer ones.

What is the best altitude to avoid turbulence on LHR-EWR?

There is no single calm level: the smooth air sits above or below the jet's shear layer, which moves day to day. Crews typically request a step climb to FL380-FL400 once the aircraft is light enough.

When is the best time of year to fly LHR-EWR?

Late spring through early autumn. The polar jet weakens in summer, so June to September flights are typically the smoothest.

What causes the turbulence on this route?

Wind shear at the edges of the polar jet stream, which produces Clear Air Turbulence, invisible to radar but well captured by WAFS forecasts.

Turbulence forecast LHR → EWR. London Heathrow to Newark. SkyBriefing.

London to Newark, New York area: what the LHR to EWR corridor looks like

Departure: London Heathrow Airport, London, the United Kingdom
Arrival: Newark Liberty International Airport, Newark, New York area, the United States
Great-circle distance: 5,563 km (3,004 nm)
Typical airborne time: 6h 58m
Usual cruise levels: FL340 to FL400
Initial track: westbound

Route overview

London Heathrow Airport (LHR) in London, the United Kingdom, to Newark Liberty International Airport (EWR) in Newark, New York area, the United States, is a great-circle distance of 5,563 km, about 3,004 nautical miles. At typical jet cruise speeds, and with an allowance for climb, descent and approach, that works out to roughly 6h 58m of airborne time. The great-circle track leaves London westbound and spends most of the flight in mid latitude air.

Leaving London

Heathrow sits in the flat Thames valley west of London. There is no terrain to shelter it, so Atlantic frontal wind reaches the field directly and makes winter climb outs the busiest phase of many flights here. The great-circle track leaves LHR westbound, and the first waypoint band of the flight sits close to 48.8N 18.9W. On a sector of 6h 58m, the climb to cruise takes roughly the first twenty to twenty five minutes.

Jet stream along the track

Along the way the track passes over the open Atlantic and high latitude airspace where the polar jet stream lives. The midpoint of the LHR to EWR track lies near 46.1N 37.3W, about 2,782 km from London, which is where the corridor spends its longest continuous stretch at cruise level. The corridor sits under the polar jet stream for much of the crossing. Where the wind speed changes sharply at the edge of that jet, the air can develop clear air turbulence, which radar cannot see but the WAFS model forecasts well. Flight planners choose a track and a level that keep the aircraft away from the strongest shear layer, and the rougher patches that remain usually last minutes at a time.

Cruise altitudes on this sector

Long haul crews normally start cruise around FL340, then step climb toward FL380 or FL400 as the aircraft burns off fuel and can hold a higher level. Choice of level matters because turbulence is layered: a change of two or three thousand feet often puts the aircraft into calmer air, and that is one of the first adjustments a crew will request.

Arriving into Newark, New York area

Arrivals into Newark are vectored over water and marshland with frequent level segments. The sea to land air boundary along the New Jersey coast is the common source of light chop on descent. Descent normally begins around 43.4N 55.7W, roughly 1,391 km before EWR, and takes about half an hour from cruise level to touchdown.

Seasonal pattern

Seasonally, the polar jet stream is strongest in the northern winter, so flights between November and March meet more clear air turbulence than the same route in June or September.

Flying this route with less worry

Turbulence on this corridor is a comfort issue rather than a safety one. Airliners are certified to handle loads well beyond anything the atmosphere produces here, crews are trained for it, and the seat belt sign is the tool that keeps the cabin settled. What this page adds is knowing in advance: the map and Calmness Score above use current WAFS forecast data for LHR to EWR, so you can see what to expect before you board.