WN4157
WN4157 (Southwest Airlines) is a multi-stop service on 20 routes, busiest San Jose to Seattle. Of 436 departures recorded from October 2024 to July 2026, 77.1% left on time, according to the US BTS.
- On-time departures77.1%of 436 flights
- Average delay11.5 min
- July 202630▼ 21.1%vs July 2025
- Cancelled1.8%
- Legs flown under this number20
Recorded departures by month
All legs under this number combined; see the leg table.
Months without data are left blank.
The most recent periods18 periods
| Period | Departures 2025 | Departures 2026 | Change vs last year |
|---|---|---|---|
| January | 1 | 25 | ▲ 2,400.0% |
| February | 10 | 27 | ▲ 170.0% |
| March | 2 | 4 | ▲ 100.0% |
| April | 26 | 28 | ▲ 7.7% |
| May | 36 | 36 | 0.0% |
| June | 38 | 30 | ▼ 21.1% |
| July | 38 | 30 | ▼ 21.1% |
| August | 29 | – | – |
| September | 26 | – | – |
| October | 26 | – | in progress |
| November | 2 | – | – |
| December | – | – | – |
| Year to date (Jan–Jul) | 151 | 180 | ▲ 19.2% |
according to the US BTS · October 2024 → July 2026
On-time departures by month
Months without data are left blank.
On time = departure within 15 minutes of schedule. Non-cancelled flights with a recorded delay only.
The most recent periods18 periods
| Period | On time 2025 | On time 2026 | Change vs last year |
|---|---|---|---|
| January | 100.0% | 82.6% | ▼ 17.4% |
| February | 90.0% | 92.3% | ▲ 2.6% |
| March | 50.0% | 50.0% | 0.0% |
| April | 84.0% | 96.4% | ▲ 14.8% |
| May | 69.4% | 83.3% | ▲ 20.0% |
| June | 84.2% | 57.1% | ▼ 32.1% |
| July | 71.1% | 44.8% | ▼ 36.9% |
| August | 71.4% | – | – |
| September | 80.8% | – | – |
| October | 76.9% | – | in progress |
| November | 100.0% | – | – |
| December | – | – | – |
| Year-to-date average (Jan–Jul) | 78.4% | 72.4% | ▼ 7.7% |
according to the US BTS · October 2024 → July 2026
Average departure delay by month
Months without data are left blank.
according to the US BTS · October 2024 → July 2026
Cancelled departures by month
Months without data are left blank.
The most recent periods18 periods
| Period | Cancelled 2025 | Cancelled 2026 | Change vs last year |
|---|---|---|---|
| January | 0 | 2 | – |
| February | 0 | 1 | – |
| March | 0 | 0 | – |
| April | 1 | 0 | ▼ 100.0% |
| May | 0 | 0 | – |
| June | 0 | 2 | – |
| July | 0 | 1 | – |
| August | 1 | – | – |
| September | 0 | – | – |
| October | 0 | – | in progress |
| November | 0 | – | – |
| December | – | – | – |
| Year to date (Jan–Jul) | 1 | 6 | ▲ 500.0% |
according to the US BTS · October 2024 → July 2026
This is a historical record of departures already flown, not a forecast for your flight.
Several legs: the headline figure averages all of them. See the leg table.
Cancellation share
- Not cancelled 98.2% 428
- Cancelled 1.8% 8
Share of all recorded flights in the period, all legs. · Oct 14, 2024 → Jul 31, 2026
On time, leg by leg
Departures within 15 minutes of schedule; small figure = departures recorded.
Legs flown under this number
6| Routes | Distance (km) | Avg delay | On time | Departures |
|---|---|---|---|---|
| SJC SEA Mineta San Jose International Airport – Seattle–Tacoma International Airport | 1,122 | 16.0 min | 68.3% | 60 |
| SAT ELP San Antonio International Airport – El Paso International Airport | 797 | -1.6 min | 93.1% | 58 |
| BWI CMH Baltimore/Washington International Thurgood Marshall Airport – John Glenn Columbus International Airport | 541 | 36.2 min | 48.2% | 57 |
| BWI MCO Baltimore/Washington International Thurgood Marshall Airport – Orlando International Airport | 1,269 | 4.9 min | 84.9% | 56 |
| STL AUS St. Louis Lambert International Airport – Austin Bergstrom International Airport | 1,161 | 10.7 min | 79.6% | 50 |
| LAS MSY Harry Reid International Airport – Louis Armstrong New Orleans International Airport | 2,409 | 13.5 min | 72.0% | 50 |
Monthly figures
| Period | Departures | With departure delay recorded | On time | Cancelled |
|---|---|---|---|---|
| October 2024 | 14 | 14 | 85.7% | 0 |
| November 2024 | 3 | 3 | 100.0% | 0 |
| December 2024 | 5 | 5 | 100.0% | 0 |
| January 2025 | 1 | 1 | 100.0% | 0 |
| February 2025 | 10 | 10 | 90.0% | 0 |
| March 2025 | 2 | 2 | 50.0% | 0 |
| April 2025 | 26 | 25 | 84.0% | 1 |
| May 2025 | 36 | 36 | 69.4% | 0 |
| June 2025 | 38 | 38 | 84.2% | 0 |
| July 2025 | 38 | 38 | 71.1% | 0 |
| August 2025 | 29 | 28 | 71.4% | 1 |
| September 2025 | 26 | 26 | 80.8% | 0 |
| October 2025 | 26 | 26 | 76.9% | 0 |
| November 2025 | 2 | 2 | 100.0% | 0 |
| January 2026 | 25 | 23 | 82.6% | 2 |
| February 2026 | 27 | 26 | 92.3% | 1 |
| March 2026 | 4 | 4 | 50.0% | 0 |
| April 2026 | 28 | 28 | 96.4% | 0 |
| May 2026 | 36 | 36 | 83.3% | 0 |
| June 2026 | 30 | 28 | 57.1% | 2 |
| July 2026 | 30 | 29 | 44.8% | 1 |