Electric City, Washington · field elev 1,593 ft
Density Altitude at Grand Coulee Dam (3W7)
Grand Coulee Dam sits at 1,593 ft, and even a typical July afternoon (88 °F) only lifts density altitude to about 3,780 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 | 28.0 | −109 ft | 32.7 | 219 ft |
| February | 32.4 | 198 ft | 39.5 | 686 ft |
| March | 41.1 | 795 ft | 50.7 | 1,438 ft |
| April | 49.2 | 1,339 ft | 60.6 | 2,087 ft |
| May | 58.3 | 1,938 ft | 70.8 | 2,739 ft |
| June | 64.9 | 2,364 ft | 77.8 | 3,178 ft |
| July | 73.5 | 2,909 ft | 87.6 | 3,780 ft |
| August | 72.6 | 2,853 ft | 86.9 | 3,738 ft |
| September | 63.7 | 2,287 ft | 76.8 | 3,116 ft |
| October | 50.1 | 1,399 ft | 60.2 | 2,061 ft |
| November | 37.0 | 515 ft | 43.0 | 923 ft |
| December | 28.5 | −74 ft | 33.1 | 247 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 3W7
DENSITY ALTITUDE
Field elevation 1,593 ft — the air behaves like 3,805 ft.
- PRESSURE ALT
- 1,594 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
- 2S8 — Wilbur
Wilbur · elev 2,183 ft
- 8W3 — Mansfield
Mansfield · elev 2,272 ft
- S97 — Anderson Field
Brewster · elev 920 ft
- 5W1 — Wilson Creek
Wilson Creek · elev 1,430 ft
- S35 — Okanogan Legion
Okanogan · elev 1,042 ft
- S10 — Lake Chelan
Chelan · elev 1,263 ft
- KOMK — Omak
Omak · elev 1,305 ft
- 43D — Odessa Municipal
Odessa · elev 1,738 ft
Frequently asked questions
How high does density altitude get at 3W7 in summer?
On a typical July afternoon — around 88 °F at the nearest NOAA normals station — density altitude at Grand Coulee Dam reaches roughly 3,780 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 3W7 on an average day?
It swings with the seasons: from roughly −109 ft at the coldest month's average temperature to about 2,909 ft at the warmest month's — all from a constant field elevation of 1,593 ft. The month-by-month table above carries the full year.
What is the field elevation of Grand Coulee Dam?
1,593 ft MSL, from the FAA NASR airport record (28-day cycle effective 2026-08-06). The identifier is 3W7 (FAA), in Electric City, Washington.