Galax Hillsville, Virginia · field elev 2,694 ft
Density Altitude at Twin County (KHLX)
Twin County sits at 2,694 ft, and even a typical July afternoon (82 °F) only lifts density altitude to about 4,791 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 | 32.9 | 1,604 ft | 42.4 | 2,248 ft |
| February | 36.0 | 1,816 ft | 46.5 | 2,521 ft |
| March | 42.7 | 2,268 ft | 53.8 | 3,001 ft |
| April | 52.0 | 2,884 ft | 64.7 | 3,702 ft |
| May | 60.6 | 3,441 ft | 72.4 | 4,187 ft |
| June | 67.9 | 3,905 ft | 78.9 | 4,589 ft |
| July | 71.4 | 4,124 ft | 82.2 | 4,791 ft |
| August | 70.1 | 4,043 ft | 80.5 | 4,687 ft |
| September | 63.9 | 3,652 ft | 74.8 | 4,336 ft |
| October | 53.3 | 2,969 ft | 65.4 | 3,747 ft |
| November | 43.1 | 2,295 ft | 54.7 | 3,060 ft |
| December | 36.1 | 1,823 ft | 45.5 | 2,455 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 KHLX
DENSITY ALTITUDE
Field elevation 2,694 ft — the air behaves like 4,779 ft.
- PRESSURE ALT
- 2,696 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 Virginia fields
- KPSK — New River Valley
Dublin · elev 2,105 ft
- KMKJ — Mountain Empire
Marion/Wytheville · elev 2,558 ft
- KBCB — Virginia Tech/Montgomery Exec
Blacksburg · elev 2,119 ft
- KMTV — Blue Ridge
Martinsville · elev 948 ft
- KJFZ — Tazewell County
Richlands · elev 2,653 ft
- KROA — Roanoke/Blacksburg Regional (Woodrum Field)
Roanoke · elev 1,175 ft
- KVJI — Virginia Highlands
Abingdon · elev 2,088 ft
- W91 — Smith Mountain Lake
Moneta · elev 892 ft
Frequently asked questions
How high does density altitude get at KHLX in summer?
On a typical July afternoon — around 82 °F at the nearest NOAA normals station — density altitude at Twin County reaches roughly 4,791 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 KHLX on an average day?
It swings with the seasons: from roughly 1,604 ft at the coldest month's average temperature to about 4,124 ft at the warmest month's — all from a constant field elevation of 2,694 ft. The month-by-month table above carries the full year.
What is the field elevation of Twin County?
2,694 ft MSL, from the FAA NASR airport record (28-day cycle effective 2026-08-06). The identifier is KHLX (ICAO) / HLX (FAA), in Galax Hillsville, Virginia.