WN4578
WN4578 (Southwest Airlines) is a multi-stop service on 16 routes, busiest Baltimore to Tampa. Of 177 departures recorded from October 2024 to July 2026, 60.1% left on time, according to the US BTS.
- On-time departures60.1%of 177 flights
- Average delay18.9 min
- July 202626▲ 62.5%vs July 2025
- Cancelled2.3%
- Legs flown under this number16
Recorded departures by month
All legs under this number combined; see the leg table.
Months without data are left blank.
The most recent periods14 periods
| Period | Departures 2025 | Departures 2026 | Change vs last year |
|---|---|---|---|
| January | – | 3 | – |
| February | – | 3 | – |
| March | 25 | 5 | ▼ 80.0% |
| April | 7 | 4 | ▼ 42.9% |
| May | – | 5 | – |
| June | 17 | 23 | ▲ 35.3% |
| July | 16 | 26 | ▲ 62.5% |
| August | 3 | – | – |
| September | – | – | – |
| October | – | – | in progress |
| November | 5 | – | – |
| December | 12 | – | – |
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 periods14 periods
| Period | On time 2025 | On time 2026 | Change vs last year |
|---|---|---|---|
| January | – | 66.7% | – |
| February | – | 66.7% | – |
| March | 72.0% | 25.0% | ▼ 65.3% |
| April | 85.7% | 50.0% | ▼ 41.7% |
| May | – | 40.0% | – |
| June | 62.5% | 52.2% | ▼ 16.5% |
| July | 75.0% | 44.0% | ▼ 41.3% |
| August | 100.0% | – | – |
| September | – | – | – |
| October | – | – | in progress |
| November | 20.0% | – | – |
| December | 33.3% | – | – |
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 periods14 periods
| Period | Cancelled 2025 | Cancelled 2026 | Change vs last year |
|---|---|---|---|
| January | – | 0 | – |
| February | – | 0 | – |
| March | 0 | 1 | – |
| April | 0 | 0 | – |
| May | – | 0 | – |
| June | 1 | 0 | ▼ 100.0% |
| July | 0 | 1 | – |
| August | 1 | – | – |
| September | – | – | – |
| October | – | – | in progress |
| November | 0 | – | – |
| 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 97.7% 173
- Cancelled 2.3% 4
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
3| Routes | Distance (km) | Avg delay | On time | Departures |
|---|---|---|---|---|
| BWI TPA Baltimore/Washington International Thurgood Marshall Airport – Tampa International Airport | 1,358 | 24.2 min | 47.9% | 49 |
| SMF SNA Sacramento International Airport – John Wayne Orange County International Airport | 650 | 10.9 min | 69.7% | 35 |
| LAX MDW Los Angeles International Airport – Chicago Midway International Airport | 2,812 | 7.0 min | 75.0% | 32 |
Monthly figures
| Period | Departures | With departure delay recorded | On time | Cancelled |
|---|---|---|---|---|
| October 2024 | 20 | 20 | 80.0% | 0 |
| November 2024 | 2 | 2 | 100.0% | 0 |
| December 2024 | 1 | 1 | 100.0% | 0 |
| March 2025 | 25 | 25 | 72.0% | 0 |
| April 2025 | 7 | 7 | 85.7% | 0 |
| June 2025 | 17 | 16 | 62.5% | 1 |
| July 2025 | 16 | 16 | 75.0% | 0 |
| August 2025 | 3 | 2 | 100.0% | 1 |
| November 2025 | 5 | 5 | 20.0% | 0 |
| December 2025 | 12 | 12 | 33.3% | 0 |
| January 2026 | 3 | 3 | 66.7% | 0 |
| February 2026 | 3 | 3 | 66.7% | 0 |
| March 2026 | 5 | 4 | 25.0% | 1 |
| April 2026 | 4 | 4 | 50.0% | 0 |
| May 2026 | 5 | 5 | 40.0% | 0 |
| June 2026 | 23 | 23 | 52.2% | 0 |
| July 2026 | 26 | 25 | 44.0% | 1 |