Loading...
Fetching the latest data.
San Francisco to Singapore — one of the longest scheduled flights operated by a US carrier.
United Airlines UA1 flies the jet-stream + mountain-wave corridor from San Francisco to Singapore. Conditions change hour to hour — view the live forecast for your departure date.
View live forecastJet-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 Rocky Mountains, 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 and early autumn. Transpacific routes are most turbulent in winter months when the polar jet is strong and positioned further south. Wind flowing over Rocky Mountains can generate mountain-wave turbulence that extends hundreds of kilometres downwind — most pronounced in winter when upper-level winds are strongest.
Full SFO to SIN route guideUnited Airlines UA1 operates between SFO and SIN. 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.
UA1 is typically operated by the B789. Aircraft swaps happen — confirm with your booking before flying.
Approximately 16h 18m direct, covering 13,582 km at a typical cruise of FL410.
Historically calmest during Late spring and early autumn. Forecast accuracy improves as you get closer to departure — within 48 hours the NOAA WAFS model is at peak skill.