Snohomish, Washington · field elev 23 ft
Density Altitude at Harvey Field (S43)
Harvey Field sits at 23 ft, and even a typical August afternoon (76 °F) only lifts density altitude to about 1,125 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 | 41.2 | −1,151 ft | 47.9 | −694 ft |
| February | 42.5 | −1,062 ft | 50.4 | −526 ft |
| March | 45.9 | −830 ft | 54.5 | −251 ft |
| April | 50.5 | −519 ft | 59.6 | 86 ft |
| May | 56.4 | −125 ft | 65.8 | 491 ft |
| June | 60.8 | 165 ft | 69.8 | 749 ft |
| July | 65.1 | 445 ft | 74.8 | 1,068 ft |
| August | 65.4 | 465 ft | 75.7 | 1,125 ft |
| September | 60.0 | 112 ft | 70.4 | 787 ft |
| October | 52.0 | −418 ft | 60.7 | 158 ft |
| November | 45.0 | −891 ft | 52.4 | −391 ft |
| December | 40.4 | −1,206 ft | 46.7 | −775 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 S43
DENSITY ALTITUDE
Field elevation 23 ft — the air behaves like 1,144 ft.
- PRESSURE ALT
- 24 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
- W16 — First Air Field
Monroe · elev 50 ft
- KPAE — Seattle Paine Field International
Everett · elev 607 ft
- W10 — Whidbey Air Park
Langley · elev 271 ft
- KAWO — Arlington Municipal
Arlington · elev 142 ft
- KBFI — Boeing Field/King County International
Seattle · elev 22 ft
- 13W — Camano Island Airfield
Stanwood · elev 145 ft
- KRNT — Renton Municipal
Renton · elev 32 ft
- KSEA — Seattle-Tacoma International
Seattle · elev 432 ft
Frequently asked questions
How high does density altitude get at S43 in summer?
On a typical August afternoon — around 76 °F at the nearest NOAA normals station — density altitude at Harvey Field reaches roughly 1,125 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 S43 on an average day?
It swings with the seasons: from roughly −1,206 ft at the coldest month's average temperature to about 465 ft at the warmest month's — all from a constant field elevation of 23 ft. The month-by-month table above carries the full year.
What is the field elevation of Harvey Field?
23 ft MSL, from the FAA NASR airport record (28-day cycle effective 2026-08-06). The identifier is S43 (FAA), in Snohomish, Washington.