Webster, South Dakota · field elev 1,858 ft
Density Altitude at The Sigurd Anderson (1D7)
The Sigurd Anderson sits at 1,858 ft, and even a typical July afternoon (81 °F) only lifts density altitude to about 3,693 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 | 11.4 | −964 ft | 20.4 | −314 ft |
| February | 15.8 | −644 ft | 25.3 | 33 ft |
| March | 28.4 | 250 ft | 38.0 | 913 ft |
| April | 42.4 | 1,212 ft | 52.9 | 1,911 ft |
| May | 55.8 | 2,101 ft | 66.4 | 2,785 ft |
| June | 66.1 | 2,766 ft | 76.0 | 3,390 ft |
| July | 71.0 | 3,076 ft | 80.9 | 3,693 ft |
| August | 69.0 | 2,950 ft | 79.0 | 3,576 ft |
| September | 60.2 | 2,387 ft | 70.7 | 3,057 ft |
| October | 45.5 | 1,420 ft | 55.4 | 2,075 ft |
| November | 30.0 | 362 ft | 38.8 | 968 ft |
| December | 17.3 | −536 ft | 25.4 | 40 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 1D7
DENSITY ALTITUDE
Field elevation 1,858 ft — the air behaves like 3,699 ft.
- PRESSURE ALT
- 1,859 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 South Dakota fields
- 8D7 — Clark County
Clark · elev 1,793 ft
- KATY — Watertown Regional
Watertown · elev 1,749 ft
- 2E6 — Groton Municipal
Groton · elev 1,310 ft
- 8D3 — Sisseton Municipal
Sisseton · elev 1,162 ft
- KBTN — Britton Municipal
Britton · elev 1,318 ft
- KABR — Aberdeen Regional
Aberdeen · elev 1,302 ft
- 1D1 — Milbank Municipal
Milbank · elev 1,118 ft
- 1D8 — Redfield Municipal
Redfield · elev 1,309 ft
Frequently asked questions
How high does density altitude get at 1D7 in summer?
On a typical July afternoon — around 81 °F at the nearest NOAA normals station — density altitude at The Sigurd Anderson reaches roughly 3,693 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 1D7 on an average day?
It swings with the seasons: from roughly −964 ft at the coldest month's average temperature to about 3,076 ft at the warmest month's — all from a constant field elevation of 1,858 ft. The month-by-month table above carries the full year.
What is the field elevation of The Sigurd Anderson?
1,858 ft MSL, from the FAA NASR airport record (28-day cycle effective 2026-08-06). The identifier is 1D7 (FAA), in Webster, South Dakota.