Seaside, Oregon · field elev 12 ft
Density Altitude at Seaside Municipal (56S)
Seaside Municipal sits at 12 ft, and even a typical September afternoon (67 °F) only lifts density altitude to about 529 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 | 45.6 | −864 ft | 51.8 | −445 ft |
| February | 45.5 | −871 ft | 52.6 | −392 ft |
| March | 46.8 | −782 ft | 54.1 | −292 ft |
| April | 49.0 | −633 ft | 56.2 | −152 ft |
| May | 53.0 | −365 ft | 59.7 | 79 ft |
| June | 56.2 | −152 ft | 62.1 | 236 ft |
| July | 59.0 | 33 ft | 65.0 | 425 ft |
| August | 60.0 | 99 ft | 66.4 | 516 ft |
| September | 58.3 | −13 ft | 66.6 | 529 ft |
| October | 53.6 | −325 ft | 61.6 | 204 ft |
| November | 48.4 | −674 ft | 55.1 | −225 ft |
| December | 44.8 | −918 ft | 51.2 | −485 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 56S
DENSITY ALTITUDE
Field elevation 12 ft — the air behaves like 555 ft.
- PRESSURE ALT
- 13 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 Oregon fields
- KAST — Astoria Regional
Astoria · elev 15 ft
- 3S7 — Nehalem Bay State
Manzanita · elev 30 ft
- 05S — Vernonia Municipal
Vernonia · elev 650 ft
- KTMK — Tillamook
Tillamook · elev 39 ft
- 4S4 — Skyport
Cornelius · elev 174 ft
- KSPB — Scappoose
Scappoose · elev 58 ft
- KHIO — Portland-Hillsboro
Portland · elev 208 ft
- KPFC — Pacific City State
Pacific City · elev 10 ft
Frequently asked questions
How high does density altitude get at 56S in summer?
On a typical September afternoon — around 67 °F at the nearest NOAA normals station — density altitude at Seaside Municipal reaches roughly 529 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 56S on an average day?
It swings with the seasons: from roughly −918 ft at the coldest month's average temperature to about 99 ft at the warmest month's — all from a constant field elevation of 12 ft. The month-by-month table above carries the full year.
What is the field elevation of Seaside Municipal?
12 ft MSL, from the FAA NASR airport record (28-day cycle effective 2026-08-06). The identifier is 56S (FAA), in Seaside, Oregon.