Langdon, North Dakota · field elev 1,608 ft
Density Altitude at Robertson Field (D55)
Robertson Field sits at 1,608 ft, and even a typical July afternoon (77 °F) only lifts density altitude to about 3,121 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 | 3.7 | −1,848 ft | 12.5 | −1,198 ft |
| February | 7.6 | −1,558 ft | 17.1 | −865 ft |
| March | 20.9 | −592 ft | 29.8 | 36 ft |
| April | 37.8 | 589 ft | 48.0 | 1,277 ft |
| May | 51.9 | 1,536 ft | 63.5 | 2,292 ft |
| June | 61.7 | 2,176 ft | 71.9 | 2,827 ft |
| July | 66.2 | 2,465 ft | 76.6 | 3,121 ft |
| August | 65.1 | 2,395 ft | 76.5 | 3,115 ft |
| September | 55.7 | 1,786 ft | 67.3 | 2,535 ft |
| October | 40.7 | 786 ft | 50.9 | 1,470 ft |
| November | 24.0 | −372 ft | 32.3 | 210 ft |
| December | 10.2 | −1,366 ft | 18.2 | −785 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 D55
DENSITY ALTITUDE
Field elevation 1,608 ft — the air behaves like 3,146 ft.
- PRESSURE ALT
- 1,609 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 North Dakota fields
- 96D — Walhalla Municipal
Walhalla · elev 953 ft
- 2C8 — Cavalier Municipal
Cavalier · elev 892 ft
- Y37 — Park River - W C Skjerven Field
Park River · elev 1,104 ft
- 9D7 — Cando Municipal
Cando · elev 1,482 ft
- 4S5 — St Thomas Municipal
St Thomas · elev 839 ft
- KDVL — Devils Lake Regional
Devils Lake · elev 1,469 ft
- 5L0 — Lakota Municipal
Lakota · elev 1,511 ft
- KGAF — Hutson Field
Grafton · elev 825 ft
Frequently asked questions
How high does density altitude get at D55 in summer?
On a typical July afternoon — around 77 °F at the nearest NOAA normals station — density altitude at Robertson Field reaches roughly 3,121 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 D55 on an average day?
It swings with the seasons: from roughly −1,848 ft at the coldest month's average temperature to about 2,465 ft at the warmest month's — all from a constant field elevation of 1,608 ft. The month-by-month table above carries the full year.
What is the field elevation of Robertson Field?
1,608 ft MSL, from the FAA NASR airport record (28-day cycle effective 2026-08-06). The identifier is D55 (FAA), in Langdon, North Dakota.