Skip to content
WanderNerd
Check a flight

Flight Reliability

WN 1637 · Southwest Airlines

This number covered several routes in this period.

One number, several routes.

Airlines reuse flight numbers, and WN 1637 moved between routes during this period. Numbers below combine all of them, so treat them as background, not a verdict. For a cleaner answer, check the route you are actually flying.

Combined across all its routes

78%
Arrive within 15 minutes
7 min
Average arrival delay
0%
Cancelled
3 min early
Median arrival delay

Based on 407 historical flights. Data through May 2026.

The breakdown

On-time by weekday
  • Mon85%(60 flights)
  • Tue68%(59 flights)
  • Wed77%(60 flights)
  • Thu77%(60 flights)
  • Fri77%(60 flights)
  • Sat85%(48 flights)
  • Sun80%(59 flights)
On-time by departure window
  • 6–9 AM89%(79 flights)
  • 9 AM–12 PM81%(86 flights)
  • 12–3 PM89%(18 flights)
  • 3–6 PM81%(93 flights)
  • 6–9 PM66%(130 flights)
On-time trend by month
45%
May

Jun 78% → May 45% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202578%40
July 202586%44
August 202586%42
September 202588%43
October 202590%31
November 202579%29
December 202571%31
January 202682%27
February 202670%27
March 202684%31
April 202667%30
May 202645%31
Departures on time
70%
Diverted
0.2%
Flights flown
406
Months covered
12

Keep nerding

Based on 407 historical flights, because apparently we checked. Historical flight data: U.S. Bureau of Transportation Statistics, June 2025 – May 2026. Data through May 2026. How we calculate this.