WN4121Southwest Airlines · DEN → SAN
live · 43m ago
Route confirmed Southwest Airlines

WN4121 DenverDEN San DiegoSAN

WN4121 by Southwest Airlines flies from Denver (DEN) to San Diego (SAN).

Right nowNext departure tomorrow Operates daily
20:35

scheduled from DEN

The route today

live boards
DENDenverModerate riskDEN delay board →
SANSan DiegoHigh riskSAN delay board →
DEN→SANevery carrier, schedules and on-time historyRoute intelligence →

Weather lens

Delay & cancellation outlook for this flight

Measured, 90-day sample
50%Chance of 15+ min delay
1.3%Chance of cancellation
+15 minTypical airport delay in this weather

Conditions at DEN and SAN are near their clear-air norm right now, so this reflects the route's recent baseline rather than a weather penalty. These figures come from both airports' records 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 →

Tomorrow at DEN

Forecast

Sat 14 Nov, local date

High11°Clikely 8°C to 13°C
Low2°Clikely 0°C to 4°C
  • 33% chance of fog

Forecast: GateWeather · incl. data from ECMWF (CC BY 4.0, modified) · Expected values for tomorrow from a forecast model, kept apart from today's measured figures.

Tomorrow at SAN

Forecast

Sat 14 Nov, local date

High22°Clikely 21°C to 23°C
Low15°Clikely 14°C to 17°C
  • 95% chance of rain

Forecast: GateWeather · incl. data from ECMWF (CC BY 4.0, modified) · Expected values for tomorrow from a forecast model, kept apart from today's measured figures.

When it flies

scheduled departures
061422
M
T
W
T
F
S
S

Each mark is a scheduled departure at its origin-local time. Today is highlighted.

Other Denver to San Diego flights today

same route · Southwest Airlines
WN4545departs 06:10
WN1308departs 08:35
WN24departs 12:05
WN1778departs 12:20
WN1779departs 14:30
WN1484departs 16:05

If WN4121 is cancelled, these are the other Southwest Airlines nonstop flights from Denver to San Diego on the same day, with scheduled departure times in DEN local time. Most flights that show a delay still operate. Rebooking usually helps only when that delay is very large. Every airline on this route →

How WN4121 actually runs

Pro Flight Search has tracked every published board update for WN4121 across the DEN and SAN boards: schedule changes, gate pushes and actual clocks. Combined risk score: 50.0/100. Based on airport operations, weather, and cached board history at DEN and SAN.

The verdict above is that record speaking, so it reflects how WN4121 operates rather than what the timetable promises. Numbers refresh as new flights operate.

Planning around WN4121? Will a delayed flight be cancelled? · Do planes make up time in the air? · How we measure

Cite this data

Journalists, bloggers, and researchers may cite this page with attribution and a link to Pro Flight Search.

Suggested citation

Pro Flight Search: WN4121 Denver to San Diego on-time performance, measured from the DEN and SAN airport boards.

Canonical URL
https://proflightsearch.com/flight/WN4121
How we measure this →