Troy, Montana · field elev 2,017 ft
Density Altitude at Troy (57S)
Troy sits at 2,017 ft, and even a typical July afternoon (87 °F) only lifts density altitude to about 4,241 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 | 27.8 | 407 ft | 32.7 | 747 ft |
| February | 31.3 | 651 ft | 39.0 | 1,179 ft |
| March | 38.9 | 1,172 ft | 49.7 | 1,896 ft |
| April | 46.0 | 1,650 ft | 59.1 | 2,512 ft |
| May | 54.9 | 2,238 ft | 69.8 | 3,195 ft |
| June | 61.0 | 2,634 ft | 75.8 | 3,571 ft |
| July | 68.1 | 3,088 ft | 86.7 | 4,241 ft |
| August | 66.8 | 3,005 ft | 86.0 | 4,199 ft |
| September | 58.3 | 2,460 ft | 74.9 | 3,515 ft |
| October | 45.6 | 1,624 ft | 56.5 | 2,343 ft |
| November | 34.9 | 899 ft | 40.6 | 1,287 ft |
| December | 27.9 | 414 ft | 32.4 | 727 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 57S
DENSITY ALTITUDE
Field elevation 2,017 ft — the air behaves like 4,259 ft.
- PRESSURE ALT
- 2,018 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
- S59 — Libby
Libby · elev 2,605 ft
- 88M — Eureka
Eureka · elev 2,672 ft
- KTHM — Thompson Falls
Thompson Falls · elev 2,467 ft
- 58S — Whitefish
Whitefish · elev 3,066 ft
- S27 — Kalispell City
Kalispell · elev 2,932 ft
- KGPI — Glacier Park International
Kalispell · elev 2,977 ft
- S34 — Plains
Plains · elev 2,467 ft
- S09 — Hot Springs
Hot Springs · elev 2,763 ft
Frequently asked questions
How high does density altitude get at 57S in summer?
On a typical July afternoon — around 87 °F at the nearest NOAA normals station — density altitude at Troy reaches roughly 4,241 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 57S on an average day?
It swings with the seasons: from roughly 407 ft at the coldest month's average temperature to about 3,088 ft at the warmest month's — all from a constant field elevation of 2,017 ft. The month-by-month table above carries the full year.
What is the field elevation of Troy?
2,017 ft MSL, from the FAA NASR airport record (28-day cycle effective 2026-08-06). The identifier is 57S (FAA), in Troy, Montana.