How long is flight LX40?

The ZRH to JFK route is the basis for the schedule. View the full route forecast and typical duration on the Turbcast route page.

Flight LX40

LX40 Turbulence ForecastSwiss · ZRH → JFK

About flight LX40

Airline: Swiss (LX)
Route: ZRH → JFK
Typical Aircraft: B777
Distance: 6,309 km
Duration: 7h 50m
Cruise Altitude: FL390

See today’s turbulence forecast

Swiss LX40 flies the jet-stream + mountain-wave corridor from Zurich to New York. Conditions change hour to hour - view the live forecast for your departure date.

View live forecast

Check LX40 on a specific date

Turbulence on the ZRH → JFK route

Jet-stream exposure on this corridor is significant. Long mid-latitude legs mean clear-air turbulence is the dominant source of bumps, typically encountered at cruise altitude. The route crosses or passes near the Alps, which can generate mountain-wave turbulence downwind when upper-level winds are strong. Westbound aircraft typically fly against the prevailing winds, adding flight time. Captains often pick altitudes that avoid the strongest headwinds, which can also mean picking cleaner-air altitudes.

Calmest season: Late spring to early autumn (May-September). The oceanic track sees its strongest jet-stream activity in the northern winter (Nov-Mar), when winds aloft are fastest and clear-air turbulence is more frequent. Wind flowing over the Alps can generate mountain-wave turbulence that extends hundreds of kilometres downwind - most pronounced in the northern winter (Nov-Mar), when upper-level winds are strongest.

Full ZRH to JFK route guide

Frequently asked questions

Is LX40 usually a bumpy flight?

Swiss LX40 operates between ZRH and JFK. Whether it’s bumpy depends on the day’s weather - Turbcast pulls live NOAA aviation-grade data so you can check the actual forecast for your departure date rather than relying on averages.

What aircraft does LX40 use?

LX40 is typically operated by the B777. Aircraft swaps happen - confirm with your booking before flying.

How long is the ZRH to JFK flight?

Approximately 7h 50m direct, covering 6,309 km at a typical cruise of FL390.

When does LX40 have the smoothest weather?

Historically calmest during Late spring to early autumn (May-September). Forecast accuracy improves as you get closer to departure - within 48 hours the NOAA WAFS model is at peak skill.