Coatesville, Pennsylvania · field elev 660 ft
Density Altitude at Chester County G O Carlson (KMQS)
Chester County G O Carlson sits at 660 ft, and even a typical July afternoon (85 °F) only lifts density altitude to about 2,509 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 | 30.2 | −1,121 ft | 38.5 | −543 ft |
| February | 32.4 | −966 ft | 41.5 | −338 ft |
| March | 40.4 | −413 ft | 50.3 | 257 ft |
| April | 51.4 | 331 ft | 62.7 | 1,074 ft |
| May | 61.5 | 996 ft | 72.8 | 1,722 ft |
| June | 69.9 | 1,538 ft | 80.8 | 2,225 ft |
| July | 75.0 | 1,861 ft | 85.4 | 2,509 ft |
| August | 73.1 | 1,741 ft | 83.4 | 2,386 ft |
| September | 66.1 | 1,294 ft | 76.5 | 1,956 ft |
| October | 54.3 | 523 ft | 64.9 | 1,217 ft |
| November | 43.8 | −181 ft | 53.6 | 477 ft |
| December | 35.0 | −785 ft | 43.1 | −229 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 KMQS
DENSITY ALTITUDE
Field elevation 660 ft — the air behaves like 2,485 ft.
- PRESSURE ALT
- 661 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 Pennsylvania fields
- N57 — New Garden
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- KOQN — Brandywine Regional
West Chester · elev 465 ft
- S37 — Smoketown
Smoketown · elev 370 ft
- N47 — Pottstown Municipal
Pottstown · elev 256 ft
- KPTW — Heritage Field
Pottstown · elev 308 ft
- KLNS — Lancaster
Lancaster · elev 403 ft
- KRDG — Reading Regional/Carl A Spaatz Field
Reading · elev 343 ft
- 08N — Keller Brothers
Lebanon · elev 550 ft
Frequently asked questions
How high does density altitude get at KMQS in summer?
On a typical July afternoon — around 85 °F at the nearest NOAA normals station — density altitude at Chester County G O Carlson reaches roughly 2,509 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 KMQS on an average day?
It swings with the seasons: from roughly −1,121 ft at the coldest month's average temperature to about 1,861 ft at the warmest month's — all from a constant field elevation of 660 ft. The month-by-month table above carries the full year.
What is the field elevation of Chester County G O Carlson?
660 ft MSL, from the FAA NASR airport record (28-day cycle effective 2026-08-06). The identifier is KMQS (ICAO) / MQS (FAA), in Coatesville, Pennsylvania.