Upper Lake, California · field elev 1,900 ft
Density Altitude at Gravelly Valley (1Q5)
Gravelly Valley sits at 1,900 ft, and even a typical July afternoon (95 °F) only lifts density altitude to about 4,599 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 | 46.1 | 1,512 ft | 57.4 | 2,257 ft |
| February | 48.9 | 1,699 ft | 61.4 | 2,516 ft |
| March | 52.4 | 1,930 ft | 66.0 | 2,811 ft |
| April | 55.8 | 2,153 ft | 70.7 | 3,109 ft |
| May | 62.0 | 2,555 ft | 78.9 | 3,621 ft |
| June | 68.4 | 2,963 ft | 87.0 | 4,117 ft |
| July | 74.7 | 3,360 ft | 95.0 | 4,599 ft |
| August | 73.4 | 3,278 ft | 94.1 | 4,545 ft |
| September | 69.5 | 3,033 ft | 90.3 | 4,317 ft |
| October | 61.1 | 2,497 ft | 78.9 | 3,621 ft |
| November | 51.2 | 1,851 ft | 64.3 | 2,702 ft |
| December | 45.3 | 1,459 ft | 56.0 | 2,166 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 1Q5
DENSITY ALTITUDE
Field elevation 1,900 ft — the air behaves like 4,599 ft.
- PRESSURE ALT
- 1,901 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
- KUKI — Ukiah Municipal
Ukiah · elev 617 ft
- O09 — Round Valley
Covelo · elev 1,434 ft
- 1O2 — Lampson Field
Lakeport · elev 1,380 ft
- D83 — Boonville
Boonville · elev 379 ft
- KWLW — Willows/Glenn County
Willows · elev 141 ft
- KLLR — Little River
Little River · elev 574 ft
- O60 — Cloverdale Municipal
Cloverdale · elev 276 ft
Frequently asked questions
How high does density altitude get at 1Q5 in summer?
On a typical July afternoon — around 95 °F at the nearest NOAA normals station — density altitude at Gravelly Valley reaches roughly 4,599 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 1Q5 on an average day?
It swings with the seasons: from roughly 1,459 ft at the coldest month's average temperature to about 3,360 ft at the warmest month's — all from a constant field elevation of 1,900 ft. The month-by-month table above carries the full year.
What is the field elevation of Gravelly Valley?
1,900 ft MSL, from the FAA NASR airport record (28-day cycle effective 2026-08-06). The identifier is 1Q5 (FAA), in Upper Lake, California.