Is turbulence dangerous?

Modern aircraft are engineered to handle even the heaviest turbulence. Turbulence is uncomfortable, but not a structural threat. Pilots can change altitude or routing to find calmer air.

Which times of day are smoothest?

Early morning and night flights tend to be smoother — thermal currents from solar heating can cause mild bumps on afternoon departures.

Why are there light bumps at cruise altitude?

At cruise altitude (around 10-12 km), wind shear from the jet stream can produce brief clear-air turbulence. It usually lasts a few minutes; the pilot turns on the seatbelt sign, sometimes adjusts routing.

How reliable is this forecast?

The forecast is computed from the winds of the ECMWF open global weather model. No weather forecast is 100%; treat this as direction, not a guarantee.

How do pilots know about turbulence ahead of time?

Before each flight, pilots get a wind map briefing, ICAO SIGMET (significant meteorological advisories), and pilot reports (PIREPs) from other aircraft. In flight, they stay in active contact with ATC and nearby aircraft.

Alaska Horizon AS2239

Portland → San Jose Turbulence Forecast

General route view · AS2239 · Alaska Horizon · Live tracking: FlightAware

Page updated: 25 Oct, 05:46 UTC

This result is not specific to a particular date or time, and it does not use the real flight route. It is a general route view between the two cities.

✓ Calm

2:00

The model shows this route as likely calm. Even if turbulence comes, modern aircraft are built to handle it.

→ How dangerous is turbulence, really? 43 years of data

Turbulence is normal. Keep your seatbelt fastened when seated and follow your crew's instructions.

Portland → San Jose Turbulence Forecast

✓ Calm

Portland → San Jose Turbulence Forecast

✓ Calm

Today's hour-by-hour view

Before your flight

What the air is usually like on this route

Route facts

Other flights on this route

FAQ

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