Flight OddsSouthwest Airlines · San Diego, CA to San Francisco, CA · 55 flights observed, 2026-01-06 to 2026-03-04 · 447 mi
WN3421 covers more than one route in the data window — the stats below are for SAN → SFO, the one it has flown most recently. The others are linked under “Other routes”.
How often is WN3421 on time?
Across 55 flights on SAN → SFO from 2026-01-06 to 2026-03-04, WN3421 arrived within 15 minutes of schedule 78% of the time. The median arrival delay was -9 min, and the worst 10% of flights arrived +100 min or later. 2% of flights were cancelled.
Delay distribution
Arrival delay for completed flights (excludes cancellations and diversions).
| Arrival | Flights | Share |
|---|---|---|
| Early / on-time | 42 | 78% |
| 16-30 min | 1 | 2% |
| 31-60 min | 4 | 7% |
| 61-120 min | 3 | 6% |
| 2+ hrs | 4 | 7% |
Performance by month
| Month | Flights | On-time | Avg delay |
|---|---|---|---|
| 2026-01 | 25 | 92% | -9 min |
| 2026-02 | 25 | 60% | +37 min |
| 2026-03 | 4 | 100% | -15 min |
Performance by day of week
| Day | Flights | On-time |
|---|---|---|
| Mon | 8 | 88% |
| Tue | 9 | 78% |
| Wed | 9 | 78% |
| Thu | 7 | 71% |
| Fri | 8 | 88% |
| Sat | 5 | 80% |
| Sun | 8 | 63% |
Other routes
Related
Based on US Department of Transportation Bureau of Transportation Statistics on-time data. Loading live conditions and full charts…