WN4637
WN4637 (Southwest Airlines) is a multi-stop service on 21 routes, busiest Phoenix to Burbank. Of 341 departures recorded from October 2024 to July 2026, 87.5% left on time, according to the US BTS.
- On-time departures87.5%of 341 flights
- Average delay5.9 min
- July 202618
- Cancelled1.5%
- Legs flown under this number21
Recorded departures by month
All legs under this number combined; see the leg table.
Months without data are left blank.
The most recent periods15 periods
| Period | Departures 2025 | Departures 2026 | Change vs last year |
|---|---|---|---|
| January | 1 | 15 | ▲ 1,400.0% |
| February | – | 27 | – |
| March | 66 | 7 | ▼ 89.4% |
| April | 21 | 35 | ▲ 66.7% |
| May | 4 | 44 | ▲ 1,000.0% |
| June | 1 | 20 | ▲ 1,900.0% |
| July | – | 18 | – |
| August | – | – | – |
| September | – | – | – |
| October | 30 | – | in progress |
| November | 3 | – | – |
| December | 4 | – | – |
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 periods15 periods
| Period | On time 2025 | On time 2026 | Change vs last year |
|---|---|---|---|
| January | 100.0% | 83.3% | ▼ 16.7% |
| February | – | 100.0% | – |
| March | 78.5% | 100.0% | ▲ 27.5% |
| April | 76.2% | 97.1% | ▲ 27.5% |
| May | 100.0% | 95.5% | ▼ 4.5% |
| June | 100.0% | 85.0% | ▼ 15.0% |
| July | – | 88.9% | – |
| August | – | – | – |
| September | – | – | – |
| October | 73.3% | – | in progress |
| November | 100.0% | – | – |
| December | 66.7% | – | – |
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 periods15 periods
| Period | Cancelled 2025 | Cancelled 2026 | Change vs last year |
|---|---|---|---|
| January | 0 | 3 | – |
| February | – | 0 | – |
| March | 1 | 0 | ▼ 100.0% |
| April | 0 | 0 | – |
| May | 0 | 0 | – |
| June | 0 | 0 | – |
| July | – | 0 | – |
| August | – | – | – |
| September | – | – | – |
| October | 0 | – | in progress |
| November | 0 | – | – |
| December | 1 | – | – |
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 98.5% 336
- Cancelled 1.5% 5
Share of all recorded flights in the period, all legs. · Oct 12, 2024 → Jul 31, 2026
On time, leg by leg
Departures within 15 minutes of schedule; small figure = departures recorded.
Legs flown under this number
4| Routes | Distance (km) | Avg delay | On time | Departures |
|---|---|---|---|---|
| PHX BUR Phoenix Sky Harbor International Airport – Hollywood Burbank/Bob Hope Airport | 593 | -4.2 min | 97.6% | 42 |
| TUS PHX Tucson International Airport – Phoenix Sky Harbor International Airport | 178 | 0.9 min | 95.0% | 40 |
| MDW LAX Chicago Midway International Airport – Los Angeles International Airport | 2,812 | 5.2 min | 85.3% | 34 |
| CLE BNA Cleveland Hopkins International Airport – Nashville International Airport | 721 | 13.9 min | 74.2% | 31 |
Monthly figures
| Period | Departures | With departure delay recorded | On time | Cancelled |
|---|---|---|---|---|
| October 2024 | 25 | 25 | 88.0% | 0 |
| November 2024 | 16 | 16 | 93.8% | 0 |
| December 2024 | 4 | 4 | 100.0% | 0 |
| January 2025 | 1 | 1 | 100.0% | 0 |
| March 2025 | 66 | 65 | 78.5% | 1 |
| April 2025 | 21 | 21 | 76.2% | 0 |
| May 2025 | 4 | 4 | 100.0% | 0 |
| June 2025 | 1 | 1 | 100.0% | 0 |
| October 2025 | 30 | 30 | 73.3% | 0 |
| November 2025 | 3 | 3 | 100.0% | 0 |
| December 2025 | 4 | 3 | 66.7% | 1 |
| January 2026 | 15 | 12 | 83.3% | 3 |
| February 2026 | 27 | 27 | 100.0% | 0 |
| March 2026 | 7 | 7 | 100.0% | 0 |
| April 2026 | 35 | 35 | 97.1% | 0 |
| May 2026 | 44 | 44 | 95.5% | 0 |
| June 2026 | 20 | 20 | 85.0% | 0 |
| July 2026 | 18 | 18 | 88.9% | 0 |