Covelo, California · field elev 1,434 ft
Density Altitude at Round Valley (O09)
Round Valley sits at 1,434 ft, and even a typical July afternoon (92 °F) only lifts density altitude to about 3,865 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 | 42.5 | 692 ft | 52.3 | 1,348 ft |
| February | 45.3 | 881 ft | 56.8 | 1,644 ft |
| March | 49.0 | 1,129 ft | 62.2 | 1,995 ft |
| April | 52.7 | 1,374 ft | 67.3 | 2,322 ft |
| May | 59.2 | 1,800 ft | 75.4 | 2,834 ft |
| June | 65.5 | 2,207 ft | 83.5 | 3,336 ft |
| July | 72.5 | 2,652 ft | 92.2 | 3,865 ft |
| August | 71.1 | 2,563 ft | 91.4 | 3,817 ft |
| September | 66.4 | 2,264 ft | 87.6 | 3,587 ft |
| October | 57.2 | 1,670 ft | 75.5 | 2,840 ft |
| November | 46.8 | 982 ft | 58.2 | 1,735 ft |
| December | 41.2 | 604 ft | 50.0 | 1,195 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 O09
DENSITY ALTITUDE
Field elevation 1,434 ft — the air behaves like 3,853 ft.
- PRESSURE ALT
- 1,435 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 California fields
- O28 — Ells Field/Willits Municipal
Willits · elev 2,066 ft
- 1Q5 — Gravelly Valley
Upper Lake · elev 1,900 ft
- T42 — Ruth
Ruth · elev 2,781 ft
- O16 — Garberville
Garberville · elev 551 ft
- KLLR — Little River
Little River · elev 574 ft
- 0Q5 — Shelter Cove
Shelter Cove · elev 73 ft
- KUKI — Ukiah Municipal
Ukiah · elev 617 ft
- D63 — Dinsmore
Dinsmore · elev 2,393 ft
Frequently asked questions
How high does density altitude get at O09 in summer?
On a typical July afternoon — around 92 °F at the nearest NOAA normals station — density altitude at Round Valley reaches roughly 3,865 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 O09 on an average day?
It swings with the seasons: from roughly 604 ft at the coldest month's average temperature to about 2,652 ft at the warmest month's — all from a constant field elevation of 1,434 ft. The month-by-month table above carries the full year.
What is the field elevation of Round Valley?
1,434 ft MSL, from the FAA NASR airport record (28-day cycle effective 2026-08-06). The identifier is O09 (FAA), in Covelo, California.