WN4578 DenverDEN · 20:55 TucsonTUS · 22:00
WN4578 by Southwest Airlines flies from Denver (DEN) to Tucson (TUS).
scheduled from DEN
⚖ WN4578 typically leaves +31 and lands +19. The air wins minutes back.Where the minutes go
last 7 operations · gate push → arrivalThe bar is how late it left the gate; the ring is where it actually arrived. Board clocks, not estimates.
The last 30 days
arrival outcome per operationmedian arrival +19 min · 0 cancelled · 9 operations tracked
The route today
live boardsWeather lens
Delay & cancellation outlook for this flight
Measured, 90-day sampleConditions at DEN and TUS 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 Denver to Tucson flights today
same route · Southwest AirlinesIf WN4578 is cancelled, these are the other Southwest Airlines nonstop flights from Denver to Tucson on the same day, with scheduled departure times in DEN local time. Most flights posting a delay still operate — rebooking usually only beats a very large posted delay. Every airline on this route →
How WN4578 actually runs
Pro Flight Search has tracked every published board update for WN4578 across the DEN and TUS boards: schedule changes, gate pushes and actual clocks. Usually lands ~19 min late. Based on 9 confirmed landings · 4/9 within 15 min of schedule. Pushes back late but makes up time in the air.
The verdict above is that record speaking, so it reflects how WN4578 operates rather than what the timetable promises. Numbers refresh as new flights operate.
How this operation is measured
Board log
scheduled → actual, per operationAircraft
Recent tails: N9007K, N8663A, N8957Q, N8647A.
Board clocks recorded as DEN and TUS published them.
Planning around WN4578? Will a delayed flight be cancelled? · Do planes make up time in the air? · How we measure
Journalists, bloggers, and researchers may cite this page with attribution and a link to Pro Flight Search.
Pro Flight Search — WN4578 Denver to Tucson on-time performance, measured from the DEN and TUS airport boards.
https://proflightsearch.com/flight/WN4578
.