Townsend, Montana · field elev 3,897 ft
Density Altitude at Townsend (8U8)
From a field elevation of 3,897 ft, a typical July afternoon at Townsend (83 °F) raises density altitude to about 6,326 ft — solidly into the range where performance charts deserve a close read.
Typical density altitude by month
| Month | Avg temp °F | DA at avg temp | Afternoon high °F | DA on a typical afternoon |
|---|---|---|---|---|
| January | 23.8 | 2,475 ft | 33.9 | 3,168 ft |
| February | 27.6 | 2,738 ft | 38.7 | 3,491 ft |
| March | 36.5 | 3,343 ft | 49.4 | 4,197 ft |
| April | 44.6 | 3,883 ft | 58.2 | 4,765 ft |
| May | 53.2 | 4,444 ft | 67.0 | 5,320 ft ▲ |
| June | 60.4 | 4,905 ft | 74.1 | 5,760 ft ▲ |
| July | 67.5 | 5,352 ft | 83.4 | 6,326 ft ▲ |
| August | 66.2 | 5,270 ft | 82.6 | 6,278 ft ▲ |
| September | 57.2 | 4,701 ft | 72.7 | 5,674 ft ▲ |
| October | 45.2 | 3,922 ft | 58.5 | 4,784 ft |
| November | 33.0 | 3,107 ft | 43.7 | 3,823 ft |
| December | 24.0 | 2,489 ft | 33.8 | 3,161 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 8U8
DENSITY ALTITUDE caution
Field elevation 3,897 ft — the air behaves like 6,302 ft.
- PRESSURE ALT
- 3,899 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 Montana fields
- 8U9 — Canyon Ferry
Townsend · elev 3,840 ft
- 7S6 — White Sulphur Springs
White Sulphur Springs · elev 5,065 ft
- KHLN — Helena Regional
Helena · elev 3,877 ft
- 3U9 — Boulder
Boulder · elev 4,968 ft
- 9S5 — Three Forks
Three Forks · elev 4,089 ft
- KBZN — Bozeman Yellowstone International
Bozeman · elev 4,473 ft
- 9U1 — Wilsall
Wilsall · elev 5,140 ft
- KBTM — Bert Mooney
Butte · elev 5,551 ft
Frequently asked questions
How high does density altitude get at 8U8 in summer?
On a typical July afternoon — around 83 °F at the nearest NOAA normals station — density altitude at Townsend reaches roughly 6,326 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 8U8 on an average day?
It swings with the seasons: from roughly 2,475 ft at the coldest month's average temperature to about 5,352 ft at the warmest month's — all from a constant field elevation of 3,897 ft. The month-by-month table above carries the full year.
What is the field elevation of Townsend?
3,897 ft MSL, from the FAA NASR airport record (28-day cycle effective 2026-08-06). The identifier is 8U8 (FAA), in Townsend, Montana.