St Charles, Missouri · field elev 437 ft
Density Altitude at St Charles County Regional/Smartt Field (KSET)
St Charles County Regional/Smartt Field sits at 437 ft, and even a typical July afternoon (89 °F) only lifts density altitude to about 2,465 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 | 30.8 | −1,357 ft | 39.7 | −738 ft |
| February | 35.4 | −1,036 ft | 45.1 | −370 ft |
| March | 45.4 | −349 ft | 56.4 | 387 ft |
| April | 56.7 | 406 ft | 68.2 | 1,155 ft |
| May | 66.6 | 1,052 ft | 77.3 | 1,733 ft |
| June | 75.4 | 1,613 ft | 85.9 | 2,268 ft |
| July | 78.6 | 1,814 ft | 89.1 | 2,465 ft |
| August | 76.9 | 1,708 ft | 87.8 | 2,385 ft |
| September | 69.1 | 1,213 ft | 81.2 | 1,977 ft |
| October | 57.5 | 459 ft | 69.3 | 1,225 ft |
| November | 45.0 | −376 ft | 55.4 | 320 ft |
| December | 35.5 | −1,029 ft | 44.1 | −438 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 KSET
DENSITY ALTITUDE
Field elevation 437 ft — the air behaves like 2,459 ft.
- PRESSURE ALT
- 438 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 Missouri fields
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- KSUS — Spirit Of St Louis
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- M71 — Greensfield
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- KFYG — Washington Regional
Washington · elev 488 ft
- H19 — Bowling Green Municipal
Bowling Green · elev 891 ft
- 63M — Hermann Municipal
Hermann · elev 508 ft
- KUUV — Sullivan Regional
Sullivan · elev 933 ft
Frequently asked questions
How high does density altitude get at KSET in summer?
On a typical July afternoon — around 89 °F at the nearest NOAA normals station — density altitude at St Charles County Regional/Smartt Field reaches roughly 2,465 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 KSET on an average day?
It swings with the seasons: from roughly −1,357 ft at the coldest month's average temperature to about 1,814 ft at the warmest month's — all from a constant field elevation of 437 ft. The month-by-month table above carries the full year.
What is the field elevation of St Charles County Regional/Smartt Field?
437 ft MSL, from the FAA NASR airport record (28-day cycle effective 2026-08-06). The identifier is KSET (ICAO) / SET (FAA), in St Charles, Missouri.