South Boston, Virginia · field elev 420 ft

Density Altitude at William M Tuck (W78)

William M Tuck sits at 420 ft, and even a typical July afternoon (90 °F) only lifts density altitude to about 2,499 ft — heat still trims performance, but the field rarely turns high-and-hot.

worst typical month: July · ≈2,499 ft station: S BOSTON · 2 mi away normals vintage 1991–2020

Typical density altitude by month

From NOAA 1991–2020 monthly normals at S BOSTON (2 mi from the field) · standard pressure, dry air
Month Avg temp °F DA at avg temp Afternoon high °F DA on a typical afternoon
January 38.6 −835 ft 50.7 −13 ft
February 41.1 −664 ft 54.0 207 ft
March 48.1 −188 ft 61.9 726 ft
April 57.5 438 ft 71.8 1,364 ft
May 66.0 992 ft 78.7 1,800 ft
June 74.3 1,523 ft 86.2 2,266 ft
July 78.7 1,800 ft 90.0 2,499 ft
August 77.1 1,699 ft 88.3 2,395 ft
September 70.8 1,300 ft 82.6 2,043 ft
October 59.3 556 ft 72.8 1,428 ft
November 48.6 −154 ft 62.6 772 ft
December 41.6 −629 ft 53.8 193 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 W78

Altimeter-style gauge: field elevation and density altitude needles 03691215 DENSITY ALT ×1,000 FT 2,499 DENSITY ALTITUDE · FEET
field elevation density altitude

DENSITY ALTITUDE 2,499 ft

Field elevation 420 ft — the air behaves like 2,499 ft.

PRESSURE ALT
421 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

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Frequently asked questions

How high does density altitude get at W78 in summer?

On a typical July afternoon — around 90 °F at the nearest NOAA normals station — density altitude at William M Tuck reaches roughly 2,499 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 W78 on an average day?

It swings with the seasons: from roughly −835 ft at the coldest month's average temperature to about 1,800 ft at the warmest month's — all from a constant field elevation of 420 ft. The month-by-month table above carries the full year.

What is the field elevation of William M Tuck?

420 ft MSL, from the FAA NASR airport record (28-day cycle effective 2026-08-06). The identifier is W78 (FAA), in South Boston, Virginia.