BY204 turbulence forecast
Thomsonfly · Birmingham (BHX) to Cancun (CUN)
Next departure at its usual time · Sun 8 Nov, 09:20 Birmingham time
This date's schedule isn't confirmed yet. This is the air BY204 flies through if it leaves at its usual time.
Smooth most of the way, with occasional light bumps after takeoff. Barely moves your drink.
- Bumpiest stretch
- Light
- Flight time
- 10h 40m
- Distance
- 8,267 km
- Cruise altitude
- 37,000 ft
- Weather models
- 4 blended
- Model agreement
- Medium
- Aircraft
- Boeing 787 Dreamliner
Bumpiness along the flight
Takeoff on the left, landing on the right. The higher the line, the bumpier the air the forecast expects at that moment.
Where, and why
The flight split into stretches: how bumpy each is forecast to be, and what causes it.
Cruise0m – 53mSmooth
Nothing significant forecast here.
At cruise the air is thin and cold, and most of it is calm. The bumps up here come from the jet stream, a band of fast wind whose edges stir the air, or from waves set off by mountains far below. This forecast shows where those edges are.
Cruise53m – 1h 39mLight
Jet-stream wind shear
Where fast air slides over slower air, usually at the edge of the jet stream, the boundary ripples like a flag. It's the most common kind of turbulence, and it's on the crew's charts before departure. When they meet it, they slow to a set turbulence speed and ride it out.
At cruise the air is thin and cold, and most of it is calm. The bumps up here come from the jet stream, a band of fast wind whose edges stir the air, or from waves set off by mountains far below. This forecast shows where those edges are.
Cruise1h 39m – 10h 40mSmooth
Nothing significant forecast here.
At cruise the air is thin and cold, and most of it is calm. The bumps up here come from the jet stream, a band of fast wind whose edges stir the air, or from waves set off by mountains far below. This forecast shows where those edges are.
This forecast changes. FlyBud tells you when.
A new weather model run lands every few hours. Add BY204 in FlyBud and you get the full turbulence map along your route, a push when the forecast for your flight changes, live tracking and your flight on the lock screen.
Flight status
The latest BY204 flight on our records, as the airline last reported it.
Last update 9 days ago
Gate changes, delays and the baggage belt, pushed to your phone as they happen.
The aircraft
What BY204 is flown with, and how it handles bumpy air.
Boeing 787-9
- Type code
- B789
- Seats on this flight
- 345
- First flew
- 2009
- In service since
- 2011
- Economy seating
- 3-3-3
- Engines
- 2
- Range
- 15,370 km
- Cabin pressure equal to
- 6,000 ft
Bigger and heavier aircraft are moved less by the same patch of air, and every airliner is designed for much stronger turbulence than it will meet.
The airline
Thomsonfly
Thomsonfly operates BY204.
The route
Birmingham (BHX) → Cancun (CUN)
- Distance
- 8,267 km
- Flight time
- 10h 40m
- Usual departure
- 09:20 local
- Usual arrival
- 15:00 local
Recent BY204 flights
The forecast each flight carried, and how it ran.
| Date | Aircraft | Forecast | How it ran |
|---|---|---|---|
| Wed 28 Oct | 787 | Light | On time |
What each level feels like
- Smooth
- Calm air. Nothing to notice beyond the hum of the engines.
- Light
- Gentle ripples and the odd dip. Drinks stay put, and walking to the toilet is fine.
- Moderate
- Clear bumps. Drinks may slosh and the belt sign comes on. Uncomfortable, but the pilots stay in full control.
- Severe
- Strong jolts, and loose items can move. This is rare, and it's why the belt sign exists. Crews slow down and change altitude to get out of it.
How this forecast is made
The planned route is sampled from gate to gate at the altitude the aircraft flies, through 4 independent global weather models, and corrected with turbulence reports radioed in by pilots in the last few hours. Each new model run replaces the forecast; nothing here is a guess from the airline's history.
The weather models behind this forecast mostly agree; the bumpy patches may shift a little.
Planned route · timing and conditions may change.
Why turbulence isn't dangerous
Aircraft are designed for much worse.
Airliners are tested to loads well beyond anything turbulence produces. The wings are meant to flex, so seeing them move is normal.
Crews know where it is.
Your crew has forecasts like this one, live reports from other pilots and their own weather radar, and they change altitude to stay out of bumpy air.
Keep your belt on.
Almost all turbulence injuries happen to people who are standing or not buckled in. Seated with your belt on, turbulence is uncomfortable but not dangerous.
Questions about BY204
Will BY204 be bumpy?
For the flight on Sun 8 Nov: Smooth most of the way, with occasional light bumps after takeoff. Barely moves your drink. The forecast is replaced with every new weather model run, so check back closer to departure.
What plane flies BY204?
Recently BY204 has been flown with: Boeing 787 Dreamliner. Airlines can swap the aircraft until shortly before departure.
How long is BY204?
About 10h 40m gate to gate from Birmingham to Cancun, a distance of about 8,267 km.
What time does BY204 leave?
BY204 usually departs Birmingham at 09:20 local time and arrives in Cancun at 15:00 local time. Times change; the app tracks the live schedule.
Is turbulence dangerous on BY204?
Turbulence is uncomfortable, not dangerous to the aircraft. Airliners are certified for loads far beyond anything turbulence produces, and crews plan around the bumpy patches with the same kind of forecast as this one. Injuries are almost always to people who were standing or unbuckled, so keep your seatbelt fastened whenever you're seated.
How accurate is this turbulence forecast?
It is a forecast, so it is best within a day or so of departure and improves with every model run. The bumpy patches it finds are usually in the right place, but their timing can shift by a few minutes and the crew may change altitude to avoid them, so the ride you get is often smoother than the forecast.
Fly BY204 knowing what's ahead
The turbulence forecast for your exact flight, live tracking, delay alerts and arrival weather. Built for people who'd rather know.