Cold Meadows Guard Station, Idaho · field elev 7,030 ft
Density Altitude at Cold Meadows Usfs (U81)
Cold Meadows Usfs is a genuine high-and-hot field: from 7,030 ft of elevation, a typical July afternoon (79 °F) pushes density altitude to about 9,872 ft — the airplane performs like it is 2,842 ft above the field before the wheels roll.
Typical density altitude by month
| Month | Avg temp °F | DA at avg temp | Afternoon high °F | DA on a typical afternoon |
|---|---|---|---|---|
| January | 21.1 | 6,191 ft | 35.0 | 7,120 ft ▲ |
| February | 24.0 | 6,387 ft | 40.8 | 7,498 ft ▲ |
| March | 31.5 | 6,889 ft | 45.7 | 7,813 ft ▲ |
| April | 35.1 | 7,126 ft | 49.8 | 8,074 ft ⚠ |
| May | 43.3 | 7,659 ft | 59.3 | 8,669 ft ⚠ |
| June | 51.1 | 8,156 ft | 68.1 | 9,208 ft ⚠ |
| July | 58.0 | 8,588 ft | 79.2 | 9,872 ft ⚠ |
| August | 56.9 | 8,520 ft | 78.9 | 9,855 ft ⚠ |
| September | 49.4 | 8,049 ft | 69.2 | 9,275 ft ⚠ |
| October | 39.4 | 7,407 ft | 56.0 | 8,464 ft ⚠ |
| November | 28.7 | 6,703 ft | 41.2 | 7,524 ft ▲ |
| December | 21.6 | 6,225 ft | 34.1 | 7,061 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 U81
DENSITY ALTITUDE high DA
Field elevation 7,030 ft — the air behaves like 9,861 ft.
- PRESSURE ALT
- 7,032 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 Idaho fields
- I08 — Cabin Creek Usfs
Big Creek Ranger Station · elev 4,289 ft
- U79 — Chamberlain Usfs
Chamberlain Guard Station · elev 5,765 ft
- 85U — Soldier Bar Usfs
Soldier Bar · elev 4,190 ft
- U60 — Big Creek
Big Creek · elev 5,743 ft
- U54 — Bernard Usfs
Bernard · elev 3,626 ft
- 4D2 — Hoodoo Meadows
Salmon · elev 8,262 ft
- C48 — Wilson Bar Usfs
Dixie · elev 2,275 ft
- A05 — Dixie Usfs
Dixie · elev 5,148 ft
Frequently asked questions
How high does density altitude get at U81 in summer?
On a typical July afternoon — around 79 °F at the nearest NOAA normals station — density altitude at Cold Meadows Usfs reaches roughly 9,872 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 U81 on an average day?
It swings with the seasons: from roughly 6,191 ft at the coldest month's average temperature to about 8,588 ft at the warmest month's — all from a constant field elevation of 7,030 ft. The month-by-month table above carries the full year.
What is the field elevation of Cold Meadows Usfs?
7,030 ft MSL, from the FAA NASR airport record (28-day cycle effective 2026-08-06). The identifier is U81 (FAA), in Cold Meadows Guard Station, Idaho.