UA4427 WashingtonIAD St LouisSTL
UA4427 by United Airlines flies from Washington (IAD) to St Louis (STL).
scheduled from IAD
The route today
live boardsWeather lens
Delay & cancellation outlook for this flight
Measured, 90-day sampleConditions at IAD and STL are near their clear-air norm right now, so this reflects the route's recent baseline rather than a weather penalty. For this route and airline, under conditions like today's, over the last 90 days.
Pro Flight Search tracking, 90 days · the weather × delay correlation study → · live weather risk by airport →
When it flies
scheduled departuresEach mark is a scheduled departure at its origin-local time. Today is highlighted.
Other Washington to St Louis flights today
same route · United AirlinesIf UA4427 is cancelled, these are the other United Airlines nonstop flights from Washington to St Louis on the same day, with scheduled departure times in IAD local time. Most flights posting a delay still operate — rebooking usually only beats a very large posted delay. Every airline on this route →
How UA4427 actually runs
Pro Flight Search has tracked every published board update for UA4427 across the IAD and STL boards: schedule changes, gate pushes and actual clocks. Combined risk score: 50.0/100. Based on airport operations, weather, and cached board history at IAD and STL.
The verdict above is that record speaking, so it reflects how UA4427 operates rather than what the timetable promises. Numbers refresh as new flights operate.
Planning around UA4427? Will a delayed flight be cancelled? · Do planes make up time in the air? · How we measure
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Pro Flight Search — UA4427 Washington to St Louis on-time performance, measured from the IAD and STL airport boards.
https://proflightsearch.com/flight/UA4427
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