WN4576
WN4576 (Southwest Airlines) is a multi-stop service on 13 routes, busiest San Jose to San Diego. Of 276 departures recorded from October 2024 to July 2026, 63.4% left on time, according to the US BTS.
- On-time departures63.4%of 276 flights
- Average delay20.3 min
- July 202616
- Cancelled2.9%
- Legs flown under this number13
Recorded departures by month
All legs under this number combined; see the leg table.
Months without data are left blank.
The most recent periods12 periods
| Period | Departures 2025 | Departures 2026 | Change vs last year |
|---|---|---|---|
| January | 10 | 26 | ▲ 160.0% |
| February | 15 | 28 | ▲ 86.7% |
| March | 6 | 31 | ▲ 416.7% |
| April | 1 | 35 | ▲ 3,400.0% |
| May | – | 34 | – |
| June | – | 20 | – |
| July | – | 16 | – |
| August | – | – | – |
| September | – | – | – |
| October | – | – | in progress |
| November | – | – | – |
| December | 1 | – | – |
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 periods12 periods
| Period | On time 2025 | On time 2026 | Change vs last year |
|---|---|---|---|
| January | 55.6% | 91.3% | ▲ 64.3% |
| February | 66.7% | 92.6% | ▲ 38.9% |
| March | 66.7% | 43.3% | ▼ 35.0% |
| April | 100.0% | 57.1% | ▼ 42.9% |
| May | – | 52.9% | – |
| June | – | 45.0% | – |
| July | – | 25.0% | – |
| August | – | – | – |
| September | – | – | – |
| October | – | – | in progress |
| November | – | – | – |
| December | 100.0% | – | – |
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 periods12 periods
| Period | Cancelled 2025 | Cancelled 2026 | Change vs last year |
|---|---|---|---|
| January | 1 | 3 | ▲ 200.0% |
| February | 0 | 1 | – |
| March | 0 | 1 | – |
| April | 0 | 0 | – |
| May | – | 0 | – |
| June | – | 0 | – |
| July | – | 0 | – |
| August | – | – | – |
| September | – | – | – |
| October | – | – | in progress |
| November | – | – | – |
| December | 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 97.1% 268
- Cancelled 2.9% 8
Share of all recorded flights in the period, all legs. · Oct 12, 2024 → Jul 29, 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 |
|---|---|---|---|---|
| SJC SAN Mineta San Jose International Airport – San Diego International Airport | 671 | 15.1 min | 67.2% | 61 |
| CLT BWI Charlotte Douglas International Airport – Baltimore/Washington International Thurgood Marshall Airport | 581 | 6.3 min | 92.6% | 58 |
| ONT LAS Ontario International Airport – Harry Reid International Airport | 317 | 30.9 min | 48.0% | 50 |
| TPA MDW Tampa International Airport – Chicago Midway International Airport | 1,607 | 29.9 min | 34.4% | 33 |
Monthly figures
| Period | Departures | With departure delay recorded | On time | Cancelled |
|---|---|---|---|---|
| October 2024 | 16 | 16 | 87.5% | 0 |
| November 2024 | 15 | 15 | 73.3% | 0 |
| December 2024 | 22 | 20 | 70.0% | 2 |
| January 2025 | 10 | 9 | 55.6% | 1 |
| February 2025 | 15 | 15 | 66.7% | 0 |
| March 2025 | 6 | 6 | 66.7% | 0 |
| April 2025 | 1 | 1 | 100.0% | 0 |
| December 2025 | 1 | 1 | 100.0% | 0 |
| January 2026 | 26 | 23 | 91.3% | 3 |
| February 2026 | 28 | 27 | 92.6% | 1 |
| March 2026 | 31 | 30 | 43.3% | 1 |
| April 2026 | 35 | 35 | 57.1% | 0 |
| May 2026 | 34 | 34 | 52.9% | 0 |
| June 2026 | 20 | 20 | 45.0% | 0 |
| July 2026 | 16 | 16 | 25.0% | 0 |