Washington, District of Columbia · field elev 192 ft
Density Altitude at Washington Manassas/Harry P Davis Field (KHEF)
Washington Manassas/Harry P Davis Field sits at 192 ft, and even a typical July afternoon (88 °F) only lifts density altitude to about 2,068 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 | 33.3 | −1,488 ft | 42.4 | −858 ft |
| February | 35.7 | −1,321 ft | 45.5 | −647 ft |
| March | 43.1 | −810 ft | 53.8 | −89 ft |
| April | 54.5 | −42 ft | 65.9 | 705 ft |
| May | 63.9 | 576 ft | 74.2 | 1,237 ft |
| June | 73.3 | 1,180 ft | 83.0 | 1,790 ft |
| July | 78.1 | 1,483 ft | 87.5 | 2,068 ft |
| August | 76.0 | 1,351 ft | 85.4 | 1,938 ft |
| September | 68.3 | 860 ft | 78.2 | 1,490 ft |
| October | 56.3 | 77 ft | 67.0 | 776 ft |
| November | 45.9 | −620 ft | 56.4 | 84 ft |
| December | 37.6 | −1,189 ft | 46.5 | −579 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 KHEF
DENSITY ALTITUDE
Field elevation 192 ft — the air behaves like 2,099 ft.
- PRESSURE ALT
- 193 ft
- ISA DEVIATION
- —
- RULE-OF-THUMB DA
- —
- AIR DENSITY INDEX
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- 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 District of Columbia fields
- KIAD — Washington Dulles International
Washington · elev 312 ft
- KDCA — Ronald Reagan Washington Ntl
Washington · elev 14 ft
Frequently asked questions
How high does density altitude get at KHEF in summer?
On a typical July afternoon — around 88 °F at the nearest NOAA normals station — density altitude at Washington Manassas/Harry P Davis Field reaches roughly 2,068 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 KHEF on an average day?
It swings with the seasons: from roughly −1,488 ft at the coldest month's average temperature to about 1,483 ft at the warmest month's — all from a constant field elevation of 192 ft. The month-by-month table above carries the full year.
What is the field elevation of Washington Manassas/Harry P Davis Field?
192 ft MSL, from the FAA NASR airport record (28-day cycle effective 2026-08-06). The identifier is KHEF (ICAO) / HEF (FAA), in Washington, District of Columbia.