Bieber, California · field elev 4,163 ft
Density Altitude at Southard Field (O55)
From a field elevation of 4,163 ft, a typical July afternoon at Southard Field (89 °F) raises density altitude to about 6,965 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 | 35.7 | 3,619 ft | 47.0 | 4,369 ft |
| February | 38.1 | 3,780 ft | 50.4 | 4,590 ft |
| March | 42.2 | 4,053 ft | 55.7 | 4,932 ft |
| April | 47.0 | 4,369 ft | 61.8 | 5,319 ft ▲ |
| May | 54.8 | 4,874 ft | 70.9 | 5,888 ft ▲ |
| June | 61.5 | 5,301 ft | 79.4 | 6,408 ft ▲ |
| July | 69.7 | 5,813 ft | 88.7 | 6,965 ft ▲ |
| August | 68.4 | 5,733 ft | 88.2 | 6,935 ft ▲ |
| September | 62.7 | 5,376 ft | 82.6 | 6,601 ft ▲ |
| October | 51.7 | 4,674 ft | 68.8 | 5,758 ft ▲ |
| November | 41.2 | 3,987 ft | 54.5 | 4,855 ft |
| December | 34.2 | 3,518 ft | 45.3 | 4,257 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 O55
DENSITY ALTITUDE caution
Field elevation 4,163 ft — the air behaves like 6,983 ft.
- PRESSURE ALT
- 4,165 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
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- A24 — California Pines
Alturas · elev 4,389 ft
- KAAT — Alturas Municipal
Alturas · elev 4,378 ft
- 1Q2 — Spaulding
Susanville · elev 5,116 ft
- O39 — Ravendale
Ravendale · elev 5,306 ft
- O81 — Tulelake Municipal
Tulelake · elev 4,049 ft
- O59 — Cedarville
Cedarville · elev 4,623 ft
Frequently asked questions
How high does density altitude get at O55 in summer?
On a typical July afternoon — around 89 °F at the nearest NOAA normals station — density altitude at Southard Field reaches roughly 6,965 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 O55 on an average day?
It swings with the seasons: from roughly 3,518 ft at the coldest month's average temperature to about 5,813 ft at the warmest month's — all from a constant field elevation of 4,163 ft. The month-by-month table above carries the full year.
What is the field elevation of Southard Field?
4,163 ft MSL, from the FAA NASR airport record (28-day cycle effective 2026-08-06). The identifier is O55 (FAA), in Bieber, California.