Seattle, Washington · field elev 22 ft
Density Altitude at Boeing Field/King County International (KBFI)
Boeing Field/King County International sits at 22 ft, and even a typical August afternoon (77 °F) only lifts density altitude to about 1,231 ft — heat still trims performance, but the field rarely turns high-and-hot.
Typical density altitude by month
| Month | Avg temp °F | DA at avg temp | Afternoon high °F | DA on a typical afternoon |
|---|---|---|---|---|
| January | 42.7 | −1,049 ft | 48.6 | −648 ft |
| February | 43.7 | −981 ft | 50.7 | −507 ft |
| March | 47.1 | −749 ft | 54.8 | −233 ft |
| April | 51.7 | −440 ft | 59.8 | 98 ft |
| May | 57.9 | −27 ft | 66.5 | 535 ft |
| June | 62.6 | 281 ft | 71.2 | 837 ft |
| July | 67.4 | 593 ft | 77.3 | 1,225 ft |
| August | 67.8 | 619 ft | 77.4 | 1,231 ft |
| September | 62.8 | 294 ft | 71.7 | 869 ft |
| October | 53.7 | −306 ft | 61.0 | 177 ft |
| November | 46.4 | −797 ft | 53.0 | −353 ft |
| December | 42.0 | −1,097 ft | 47.8 | −702 ft |
▲ above 5,000 ft · ⚠ above 8,000 ft. These are planning references at standard pressure and dry air — afternoon humidity and low pressure both push the real number higher. Run today's values below.
Run today’s numbers for KBFI
DENSITY ALTITUDE
Field elevation 22 ft — the air behaves like 1,206 ft.
- PRESSURE ALT
- 23 ft
- ISA DEVIATION
- —
- RULE-OF-THUMB DA
- —
- AIR DENSITY INDEX
- —
- AIR DENSITY
- —
- WATER · GRAINS/LB
- —
For training and reference · verify with official sources and your POH before flight · no tool on this site renders a go / no-go judgment
Nearby Washington fields
- KRNT — Renton Municipal
Renton · elev 32 ft
- KSEA — Seattle-Tacoma International
Seattle · elev 432 ft
- 2S1 — Vashon Municipal
Vashon · elev 316 ft
- S50 — Auburn Municipal
Auburn · elev 63 ft
- S36 — Crest Airfield
Covington · elev 472 ft
- KPWT — Bremerton Ntl
Bremerton · elev 444 ft
- 8W5 — Apex Airpark
Silverdale · elev 525 ft
- KTIW — Tacoma Narrows
Tacoma · elev 295 ft
Frequently asked questions
How high does density altitude get at KBFI in summer?
On a typical August afternoon — around 77 °F at the nearest NOAA normals station — density altitude at Boeing Field/King County International reaches roughly 1,231 ft at standard pressure. Hotter-than-normal days, low pressure, and humidity all push it higher, so run the day's actual numbers before flying.
What is the density altitude at KBFI on an average day?
It swings with the seasons: from roughly −1,097 ft at the coldest month's average temperature to about 619 ft at the warmest month's — all from a constant field elevation of 22 ft. The month-by-month table above carries the full year.
What is the field elevation of Boeing Field/King County International?
22 ft MSL, from the FAA NASR airport record (28-day cycle effective 2026-08-06). The identifier is KBFI (ICAO) / BFI (FAA), in Seattle, Washington.