Graniteville, South Carolina · field elev 540 ft
Density Altitude at Twin Lakes (S17)
Twin Lakes sits at 540 ft, and even a typical July afternoon (93 °F) only lifts density altitude to about 2,828 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 | 44.0 | −316 ft | 55.4 | 448 ft |
| February | 47.2 | −100 ft | 59.2 | 698 ft |
| March | 53.9 | 348 ft | 66.9 | 1,198 ft |
| April | 62.1 | 887 ft | 75.6 | 1,752 ft |
| May | 70.3 | 1,416 ft | 83.4 | 2,239 ft |
| June | 77.4 | 1,865 ft | 89.7 | 2,627 ft |
| July | 80.9 | 2,084 ft | 93.0 | 2,828 ft |
| August | 79.3 | 1,984 ft | 90.8 | 2,694 ft |
| September | 73.9 | 1,645 ft | 85.5 | 2,369 ft |
| October | 63.4 | 972 ft | 75.9 | 1,771 ft |
| November | 53.1 | 295 ft | 65.8 | 1,127 ft |
| December | 46.4 | −154 ft | 57.9 | 613 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 S17
DENSITY ALTITUDE
Field elevation 540 ft — the air behaves like 2,828 ft.
- PRESSURE ALT
- 541 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 Carolina fields
- 6J6 — Edgefield County
Trenton · elev 611 ft
- KAIK — Aiken Regional
Aiken · elev 529 ft
- 6J4 — Saluda County
Saluda · elev 539 ft
- S19 — Mc Cormick County
Mc Cormick · elev 459 ft
- 6J0 — Lexington County
Pelion · elev 452 ft
- KBNL — Barnwell Regional
Barnwell · elev 246 ft
- KGRD — Greenwood County
Greenwood · elev 631 ft
- KCAE — Columbia Metro
Columbia · elev 236 ft
Frequently asked questions
How high does density altitude get at S17 in summer?
On a typical July afternoon — around 93 °F at the nearest NOAA normals station — density altitude at Twin Lakes reaches roughly 2,828 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 S17 on an average day?
It swings with the seasons: from roughly −316 ft at the coldest month's average temperature to about 2,084 ft at the warmest month's — all from a constant field elevation of 540 ft. The month-by-month table above carries the full year.
What is the field elevation of Twin Lakes?
540 ft MSL, from the FAA NASR airport record (28-day cycle effective 2026-08-06). The identifier is S17 (FAA), in Graniteville, South Carolina.