Route turbulence forecast
Bangkok → Tokyo
Turbulence forecast for flights from Suvarnabhumi Airport (BKK) to Narita International Airport (NRT).
Check flights on this route
Get a segment-by-segment turbulence forecast for any scheduled flight from BKK to NRT, with live wind and pilot reports.
Live status with real-time delays and cancellations.
What to expect on this route
Eastbound (generally tailwind-assisted) · Great-circle bearing 51°
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 Japanese Alps, which can generate mountain-wave turbulence downwind when upper-level winds are strong. Flying eastbound, aircraft usually benefit from tailwinds near the jet core, which trims flight time — but the edges of the jet are where clear-air turbulence most often sits.
- Mountain crossings
- Japanese Alps
- Ocean / water segments
- Indian Ocean · North Pacific
Seasonal turbulence pattern
This corridor is most turbulent in the northern winter (Nov–Mar), when the jet stream is strongest and sits closer to the route. Wind flowing over the Japanese 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.
- Peak turbulence
- November–March (Northern Hemisphere winter)
- Typically calmest
- Late spring to early autumn (May–September)
BKK → NRT turbulence FAQ
Is the Bangkok to Tokyo flight usually bumpy?
Most of the 4,649 km route sits in the mixed band with high jet-stream exposure. Historically that means occasional clear-air turbulence at cruise altitude is normal, especially in winter. Mountain-wave effects near the Japanese Alps add short bumpy stretches when upper-level winds are strong.
When is the best time to fly BKK to NRT for a smooth flight?
Statistically, Late spring to early autumn (May–September) sees the calmest conditions for this corridor. Within any season, morning departures see less convective (thunderstorm-driven) turbulence than afternoon flights.
How long is the flight from BKK to NRT?
Block time is usually around 5h 54m direct, cruising at approximately FL390 (39,000 ft). Actual duration varies with winds — tailwinds can shave 15–30 minutes, headwinds can add 30+ minutes on this eastbound sector.
How accurate is Turbcast's forecast for this route?
We use live NOAA Aviation Weather Center pilot reports (PIREPs), SIGMETs and AIRMETs, layered with physics-based Ellrod and Richardson-number calculations from Open-Meteo pressure-level wind and temperature data. If a source is unavailable for a waypoint we show an em dash rather than invent a value.
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