Eureka, California · field elev 20 ft
Density Altitude at Samoa Field (O33)
Samoa Field sits at 20 ft, and even a typical August afternoon (64 °F) only lifts density altitude to about 370 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 | 47.9 | −698 ft | 55.1 | −215 ft |
| February | 48.4 | −664 ft | 55.4 | −195 ft |
| March | 49.2 | −610 ft | 56.1 | −149 ft |
| April | 50.8 | −502 ft | 57.4 | −63 ft |
| May | 53.7 | −308 ft | 59.6 | 82 ft |
| June | 56.0 | −155 ft | 61.9 | 233 ft |
| July | 57.7 | −43 ft | 63.1 | 312 ft |
| August | 58.5 | 10 ft | 64.0 | 370 ft |
| September | 57.2 | −76 ft | 63.9 | 364 ft |
| October | 54.3 | −268 ft | 61.9 | 233 ft |
| November | 50.5 | −523 ft | 57.8 | −36 ft |
| December | 47.4 | −732 ft | 54.7 | −242 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 O33
DENSITY ALTITUDE
Field elevation 20 ft — the air behaves like 370 ft.
- PRESSURE ALT
- 21 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
- KEKA — Murray Field
Eureka · elev 11 ft
- KACV — California Redwood Coast-Humboldt County
Arcata/Eureka · elev 222 ft
- O19 — Kneeland
Eureka · elev 2,741 ft
- KFOT — Rohnerville
Fortuna · elev 393 ft
- O21 — Hoopa
Hoopa · elev 356 ft
- D63 — Dinsmore
Dinsmore · elev 2,393 ft
- H47 — Hyampom
Hyampom · elev 1,277 ft
- S51 — Andy Mc Beth
Klamath Glen · elev 42 ft
Frequently asked questions
How high does density altitude get at O33 in summer?
On a typical August afternoon — around 64 °F at the nearest NOAA normals station — density altitude at Samoa Field reaches roughly 370 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 O33 on an average day?
It swings with the seasons: from roughly −732 ft at the coldest month's average temperature to about 10 ft at the warmest month's — all from a constant field elevation of 20 ft. The month-by-month table above carries the full year.
What is the field elevation of Samoa Field?
20 ft MSL, from the FAA NASR airport record (28-day cycle effective 2026-08-06). The identifier is O33 (FAA), in Eureka, California.