Two Harbors, Minnesota · field elev 1,073 ft
Density Altitude at Richard B Helgeson (KTWM)
Richard B Helgeson sits at 1,073 ft, and even a typical July afternoon (77 °F) only lifts density altitude to about 2,511 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 | 10.3 | −2,034 ft | 19.6 | −1,357 ft |
| February | 14.2 | −1,748 ft | 25.3 | −950 ft |
| March | 26.0 | −900 ft | 36.9 | −139 ft |
| April | 38.5 | −29 ft | 49.6 | 722 ft |
| May | 51.0 | 815 ft | 63.7 | 1,647 ft |
| June | 60.2 | 1,420 ft | 72.3 | 2,197 ft |
| July | 65.4 | 1,757 ft | 77.3 | 2,511 ft |
| August | 63.7 | 1,647 ft | 74.8 | 2,354 ft |
| September | 55.2 | 1,093 ft | 65.8 | 1,782 ft |
| October | 42.7 | 257 ft | 51.4 | 842 ft |
| November | 28.7 | −710 ft | 36.1 | −194 ft |
| December | 16.1 | −1,610 ft | 24.0 | −1,042 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 KTWM
DENSITY ALTITUDE
Field elevation 1,073 ft — the air behaves like 2,492 ft.
- PRESSURE ALT
- 1,074 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 Minnesota fields
- KDLH — Duluth International
Duluth · elev 1,428 ft
- KDYT — Sky Harbor
Duluth · elev 609 ft
- KCOQ — Cloquet/Carlton County
Cloquet · elev 1,279 ft
- KEVM — Eveleth/Virginia Municipal
Eveleth · elev 1,376 ft
- KELO — Ely Municipal
Ely · elev 1,456 ft
- KHIB — Range Regional
Hibbing · elev 1,354 ft
- 12D — Tower Municipal
Tower · elev 1,370 ft
- KMZH — Moose Lake Carlton County
Moose Lake · elev 1,076 ft
Frequently asked questions
How high does density altitude get at KTWM in summer?
On a typical July afternoon — around 77 °F at the nearest NOAA normals station — density altitude at Richard B Helgeson reaches roughly 2,511 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 KTWM on an average day?
It swings with the seasons: from roughly −2,034 ft at the coldest month's average temperature to about 1,757 ft at the warmest month's — all from a constant field elevation of 1,073 ft. The month-by-month table above carries the full year.
What is the field elevation of Richard B Helgeson?
1,073 ft MSL, from the FAA NASR airport record (28-day cycle effective 2026-08-06). The identifier is KTWM (ICAO) / TWM (FAA), in Two Harbors, Minnesota.