North Sioux City, South Dakota · field elev 1,109 ft

Density Altitude at Graham Field (7K7)

Graham Field sits at 1,109 ft, and even a typical July afternoon (86 °F) only lifts density altitude to about 3,075 ft — heat still trims performance, but the field rarely turns high-and-hot.

worst typical month: July · ≈3,075 ft station: SIOUX CITY ANG · 11 mi away normals vintage 1991–2020

Typical density altitude by month

From NOAA 1991–2020 monthly normals at SIOUX CITY ANG (11 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 19.2 −1,340 ft 29.7 −594 ft
February 23.5 −1,032 ft 34.6 −253 ft
March 35.6 −184 ft 47.4 619 ft
April 47.7 639 ft 60.7 1,497 ft
May 59.4 1,413 ft 71.6 2,196 ft
June 70.0 2,095 ft 82.1 2,853 ft
July 74.5 2,379 ft 85.7 3,075 ft
August 72.0 2,222 ft 83.0 2,909 ft
September 64.1 1,717 ft 77.3 2,555 ft
October 50.6 833 ft 63.8 1,698 ft
November 35.8 −170 ft 47.3 613 ft
December 23.8 −1,011 ft 33.9 −302 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 7K7

Altimeter-style gauge: field elevation and density altitude needles 03691215 DENSITY ALT ×1,000 FT 3,093 DENSITY ALTITUDE · FEET
field elevation density altitude

DENSITY ALTITUDE 3,093 ft

Field elevation 1,109 ft — the air behaves like 3,093 ft.

PRESSURE ALT
1,110 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 Dakota fields

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Frequently asked questions

How high does density altitude get at 7K7 in summer?

On a typical July afternoon — around 86 °F at the nearest NOAA normals station — density altitude at Graham Field reaches roughly 3,075 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 7K7 on an average day?

It swings with the seasons: from roughly −1,340 ft at the coldest month's average temperature to about 2,379 ft at the warmest month's — all from a constant field elevation of 1,109 ft. The month-by-month table above carries the full year.

What is the field elevation of Graham Field?

1,109 ft MSL, from the FAA NASR airport record (28-day cycle effective 2026-08-06). The identifier is 7K7 (FAA), in North Sioux City, South Dakota.