Flight WN3999
Southwest Airlines flight WN3999
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Watch Ground Delay Program SAN
Ground Delay Program at San Diego International Airport (SAN): Average 37 minutes, up to 1 hour and 11 minutes
Reason: airport volume
Airport status
St Louis (STL) to Orlando (MCO)
Historically, this flight arrives 15+ minutes late 7% of the time, and when it is late the delay averages 73 minutes. It was cancelled 0.0% of the time.
- On-time arrivals
- 93.1%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 73 min
- Flights arriving 15+ minutes late
- Flights tracked
- 58
- Scheduled flights in the period
What caused the delays
- Late-arriving aircraft 75%
- Air traffic control & airport 20%
- Extreme weather 5%
- Airline (crew, maintenance, cleaning) 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Sacramento (SMF) to San Diego (SAN)
Historically, this flight arrives 15+ minutes late 11% of the time, and when it is late the delay averages 101 minutes. It was cancelled 0.0% of the time.
- On-time arrivals
- 88.9%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 101 min
- Flights arriving 15+ minutes late
- Flights tracked
- 27
- Scheduled flights in the period
What caused the delays
- Air traffic control & airport 70%
- Late-arriving aircraft 24%
- Airline (crew, maintenance, cleaning) 6%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Tampa (TPA) to Austin (AUS)
Historically, this flight arrives 15+ minutes late 23% of the time, and when it is late the delay averages 34 minutes. It was cancelled 0.0% of the time.
- On-time arrivals
- 76.9%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 34 min
- Flights arriving 15+ minutes late
- Flights tracked
- 27
- Scheduled flights in the period
What caused the delays
- Air traffic control & airport 79%
- Airline (crew, maintenance, cleaning) 15%
- Late-arriving aircraft 6%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
San Diego (SAN) to Denver (DEN)
Historically, this flight arrives 15+ minutes late 33% of the time, and when it is late the delay averages 84 minutes. It was cancelled 0.0% of the time.
- On-time arrivals
- 66.7%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 84 min
- Flights arriving 15+ minutes late
- Flights tracked
- 21
- Scheduled flights in the period
What caused the delays
- Air traffic control & airport 56%
- Late-arriving aircraft 41%
- Airline (crew, maintenance, cleaning) 3%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Las Vegas (LAS) to Tucson (TUS)
Only 18 flights on record, which is too few for reliable odds.
- On-time arrivals
- 72.2%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 35 min
- Flights arriving 15+ minutes late
- Flights tracked
- 18
- Scheduled flights in the period
What caused the delays
- Late-arriving aircraft 57%
- Airline (crew, maintenance, cleaning) 43%
- Air traffic control & airport 0%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Oakland (OAK) to Eugene (EUG)
Only 18 flights on record, which is too few for reliable odds.
- On-time arrivals
- 61.1%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 36 min
- Flights arriving 15+ minutes late
- Flights tracked
- 18
- Scheduled flights in the period
What caused the delays
- Air traffic control & airport 46%
- Late-arriving aircraft 32%
- Airline (crew, maintenance, cleaning) 22%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Las Vegas (LAS) to San Jose (SJC)
Only 13 flights on record, which is too few for reliable odds.
- On-time arrivals
- 76.9%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 41 min
- Flights arriving 15+ minutes late
- Flights tracked
- 13
- Scheduled flights in the period
What caused the delays
- Late-arriving aircraft 60%
- Airline (crew, maintenance, cleaning) 40%
- Air traffic control & airport 0%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Portland (PDX) to Sacramento (SMF)
Only 13 flights on record, which is too few for reliable odds.
- On-time arrivals
- 84.6%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 39 min
- Flights arriving 15+ minutes late
- Flights tracked
- 13
- Scheduled flights in the period
What caused the delays
- Late-arriving aircraft 67%
- Air traffic control & airport 33%
- Airline (crew, maintenance, cleaning) 0%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
San Diego (SAN) to Kansas City (MCI)
Only 10 flights on record, which is too few for reliable odds.
- On-time arrivals
- 90.0%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 183 min
- Flights arriving 15+ minutes late
- Flights tracked
- 10
- Scheduled flights in the period
What caused the delays
- Airline (crew, maintenance, cleaning) 100%
- Late-arriving aircraft 0%
- Air traffic control & airport 0%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Columbus (CMH) to Las Vegas (LAS)
Only 8 flights on record, which is too few for reliable odds.
- On-time arrivals
- 75.0%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 49 min
- Flights arriving 15+ minutes late
- Flights tracked
- 8
- Scheduled flights in the period
What caused the delays
- Late-arriving aircraft 90%
- Air traffic control & airport 7%
- Airline (crew, maintenance, cleaning) 3%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Columbus (CMH) to Orlando (MCO)
Only 8 flights on record, which is too few for reliable odds.
- On-time arrivals
- 62.5%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 86 min
- Flights arriving 15+ minutes late
- Flights tracked
- 8
- Scheduled flights in the period
What caused the delays
- Late-arriving aircraft 84%
- Air traffic control & airport 11%
- Airline (crew, maintenance, cleaning) 5%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Eugene (EUG) to Denver (DEN)
Only 5 flights on record, which is too few for reliable odds.
- On-time arrivals
- 0.0%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 37 min
- Flights arriving 15+ minutes late
- Flights tracked
- 5
- Scheduled flights in the period
What caused the delays
- Late-arriving aircraft 83%
- Airline (crew, maintenance, cleaning) 13%
- Air traffic control & airport 4%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Minneapolis (MSP) to Phoenix (PHX)
Only 5 flights on record, which is too few for reliable odds.
- On-time arrivals
- 60.0%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- 50 min
- Flights arriving 15+ minutes late
- Flights tracked
- 5
- Scheduled flights in the period
What caused the delays
- Airline (crew, maintenance, cleaning) 55%
- Late-arriving aircraft 26%
- Air traffic control & airport 19%
- Extreme weather 0%
- Security 0%
Share of delay minutes airlines attributed to each cause (BTS).
Chicago (MDW) to Washington (DCA)
Only 3 flights on record, which is too few for reliable odds.
- On-time arrivals
- 100.0%
- Less than 15 minutes late
- Cancelled
- 33.3%
- Of scheduled flights
- Average delay when late
- —
- Flights arriving 15+ minutes late
- Flights tracked
- 3
- Scheduled flights in the period
Phoenix (PHX) to Kansas City (MCI)
Only 1 flight on record, which is too few for reliable odds.
- On-time arrivals
- 100.0%
- Less than 15 minutes late
- Cancelled
- 0.0%
- Of scheduled flights
- Average delay when late
- —
- Flights arriving 15+ minutes late
- Flights tracked
- 1
- Scheduled flights in the period
Show as table
| Month | On time | Flights |
|---|---|---|
| September 2025 | 81.2% | 69 |
| October 2025 | 100.0% | 2 |
| November 2025 | 63.2% | 19 |
| December 2025 | 52.9% | 17 |
| January 2026 | 60.0% | 5 |
| February 2026 | 100.0% | 4 |
| March 2026 | 68.2% | 22 |
| April 2026 | 100.0% | 28 |
| May 2026 | 87.1% | 31 |
| June 2026 | 64.3% | 15 |
| July 2026 | 100.0% | 14 |
| August 2026 | 55.6% | 9 |
Source: U.S. DOT Bureau of Transportation Statistics on-time data, September 2025 – August 2026. Covers flights operated by reporting U.S. carriers. About our data