Tracker site Turbli, using data from governmental weather agencies the United Kingdom’s Met Office, as well as NOAA (United States), ECMWF (Europe), and JMA (Japan), among others has revealed its yearly ranking for the flight routes where aircraft and, of course, passengers and crew, are most likely to experience turbulence.
When it comes to air turbulence, flight routes across major mountain ranges take the top spots for the bumpiest journeys and the worst culprits in the world are journeys that overfly the Andes and the Himalaya. Unsurprisingly then, when it comes to Europe, flights over the Alps are the ones to watch out for.
Nice to Geneva is the worst European route
The number one spot in 2025 in Europe is taken by planes flying from Nice, capital of the Alps-Maritime region in southern France, to Geneva in Switzerland, surrounded by the Alps and the Jura mountains.
In fact, Nice, in a region where Mediterranean coastal weather systems meet a wall of mountains rising from the sea, features three times in the list – at number two spot (Nice to Zurich) and again at number five (Nice to Basel). Alps-Maritime airport also features at number seven.
Why do the Alps create turbulent conditions?
Turbli explains why. “Strong turbulence is generated at regions with significant velocity differences. That is when a stream of air traveling at large velocities encounters another stream at a lower speed. Such turbulence is usually encountered at jet stream boundaries, mountain waves and in the vertical currents of cumulonimbus cloud storms,” the site says.
It goes on. “Mountains act as a giant barrier for air flows. The side of the mountain facing the air is usually not very turbulent. There is just not much room for it. The air is pressed against the mountain, rises fast and reaches the peak. It’s on the back side where things can get shaky.” That’s because: “the air going downhill will reach the denser air from below and experience an upwards buoyancy force. It will raise again, reach low-density air, be pushed down again by buoyancy, and so forth.”
The most turbulent routes in Europe
The flight routes in the European top 10 all experience such conditions and sometimes pilots (and passengers) can even spot potential turbulence up ahead in the form of “lenticular clouds” which indicate hot, moist air meeting cold air – the perfect conditions to create a bumpy ride.
Luckily for the air routes on the list and the regions they serve, their geographical position near coasts and mountains gives them such spectacular scenery that people are unlikely to stop flying there any time soon.
1. Nice (NCE) – Geneva (GVA)
2. Nice – Zurich (ZRH)
3. Milan (MXP) – Zurich
4. Ferno (MXP) – Lyon (LYS)
5. Nice (NCE) – Basel (BSL)
6. Geneva (GVA) – Zurich (ZRH)
7. Alpes-Maritimes (NCE) – Lyon (LYS)
8. Geneva (GVA) – Venezia (VCE)
9. Lyon (MRS) – Zurich (ZRH)
10. Venezia (VCE) – Zurich (ZRH)
