Koyukuk, Alaska · field elev 149 ft
Density Altitude at Koyukuk (PFKU)
Koyukuk sits at 149 ft, and even a typical July afternoon (69 °F) only lifts density altitude to about 878 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 | −9.8 | −4,735 ft | −2.7 | −4,183 ft |
| February | −0.3 | −3,999 ft | 9.0 | −3,297 ft |
| March | 6.9 | −3,454 ft | 18.6 | −2,591 ft |
| April | 27.2 | −1,972 ft | 37.7 | −1,235 ft |
| May | 45.6 | −693 ft | 56.6 | 44 ft |
| June | 58.0 | 136 ft | 68.7 | 833 ft |
| July | 60.2 | 281 ft | 69.4 | 878 ft |
| August | 54.0 | −129 ft | 62.4 | 425 ft |
| September | 43.5 | −837 ft | 51.7 | −282 ft |
| October | 25.5 | −2,093 ft | 31.4 | −1,675 ft |
| November | 5.5 | −3,559 ft | 11.6 | −3,104 ft |
| December | −4.4 | −4,314 ft | 2.7 | −3,771 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 PFKU
DENSITY ALTITUDE
Field elevation 149 ft — the air behaves like 852 ft.
- PRESSURE ALT
- 150 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 Alaska fields
- PANU — Nulato
Nulato · elev 406 ft
- PAGA — Edward G Pitka Sr
Galena · elev 154 ft
- PAKV — Kaltag
Kaltag · elev 181 ft
- PARY — Ruby
Ruby · elev 658 ft
- PAHL — Huslia
Huslia · elev 220 ft
- PAKK — Koyuk Alfred Adams
Koyuk · elev 162 ft
- Z48 — Bear Creek 3
Bear Creek · elev 740 ft
- PFSH — Shaktoolik
Shaktoolik · elev 24 ft
Frequently asked questions
How high does density altitude get at PFKU in summer?
On a typical July afternoon — around 69 °F at the nearest NOAA normals station — density altitude at Koyukuk reaches roughly 878 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 PFKU on an average day?
It swings with the seasons: from roughly −4,735 ft at the coldest month's average temperature to about 281 ft at the warmest month's — all from a constant field elevation of 149 ft. The month-by-month table above carries the full year.
What is the field elevation of Koyukuk?
149 ft MSL, from the FAA NASR airport record (28-day cycle effective 2026-08-06). The identifier is PFKU (ICAO) / KYU (FAA), in Koyukuk, Alaska.