Hamilton, Montana · field elev 3,636 ft
Density Altitude at Ravalli County (KHRF)
From a field elevation of 3,636 ft, a typical July afternoon at Ravalli County (84 °F) raises density altitude to about 6,045 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 | 27.0 | 2,371 ft | 35.1 | 2,925 ft |
| February | 29.3 | 2,530 ft | 39.2 | 3,201 ft |
| March | 36.7 | 3,033 ft | 48.9 | 3,843 ft |
| April | 43.4 | 3,481 ft | 56.1 | 4,310 ft |
| May | 51.9 | 4,038 ft | 65.5 | 4,907 ft |
| June | 58.9 | 4,489 ft | 73.0 | 5,374 ft ▲ |
| July | 66.8 | 4,989 ft | 84.0 | 6,045 ft ▲ |
| August | 65.0 | 4,876 ft | 82.4 | 5,949 ft ▲ |
| September | 56.2 | 4,316 ft | 71.9 | 5,306 ft ▲ |
| October | 43.9 | 3,514 ft | 56.8 | 4,355 ft |
| November | 32.9 | 2,776 ft | 42.6 | 3,428 ft |
| December | 25.7 | 2,282 ft | 33.5 | 2,817 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 KHRF
DENSITY ALTITUDE caution
Field elevation 3,636 ft — the air behaves like 6,045 ft.
- PRESSURE ALT
- 3,638 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
- 32S — Stevensville
Stevensville · elev 3,614 ft
- 4U7 — West Fork Lodge
Conner · elev 4,249 ft
- U05 — Riddick Field
Philipsburg · elev 5,219 ft
- RC0 — Rock Creek
Clinton · elev 3,547 ft
- KMSO — Missoula Montana
Missoula · elev 3,206 ft
- M26 — Drummond
Drummond · elev 4,245 ft
- 7S4 — Wisdom
Wisdom · elev 6,133 ft
- 3U3 — Bowman Field
Anaconda · elev 5,034 ft
Frequently asked questions
How high does density altitude get at KHRF in summer?
On a typical July afternoon — around 84 °F at the nearest NOAA normals station — density altitude at Ravalli County reaches roughly 6,045 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 KHRF on an average day?
It swings with the seasons: from roughly 2,282 ft at the coldest month's average temperature to about 4,989 ft at the warmest month's — all from a constant field elevation of 3,636 ft. The month-by-month table above carries the full year.
What is the field elevation of Ravalli County?
3,636 ft MSL, from the FAA NASR airport record (28-day cycle effective 2026-08-06). The identifier is KHRF (ICAO) / HRF (FAA), in Hamilton, Montana.