Black Rapids, Alaska · field elev 2,125 ft

Density Altitude at Black Rapids (5BK)

Black Rapids sits at 2,125 ft, and even a typical July afternoon (66 °F) only lifts density altitude to about 3,081 ft — heat still trims performance, but the field rarely turns high-and-hot.

worst typical month: July · ≈3,081 ft station: GLENNALLEN 64 N · 37 mi away normals vintage 1991–2020

Typical density altitude by month

From NOAA 1991–2020 monthly normals at GLENNALLEN 64 N (37 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 −1.8 −1,606 ft 6.5 −987 ft
February 4.2 −1,157 ft 15.2 −352 ft
March 9.8 −744 ft 22.4 162 ft
April 26.0 416 ft 37.0 1,177 ft
May 40.4 1,408 ft 50.9 2,109 ft
June 50.7 2,096 ft 62.6 2,870 ft
July 54.5 2,346 ft 65.9 3,081 ft
August 49.9 2,043 ft 60.1 2,709 ft
September 40.9 1,442 ft 50.5 2,083 ft
October 24.4 304 ft 32.6 875 ft
November 5.5 −1,060 ft 14.7 −388 ft
December 1.1 −1,388 ft 11.0 −657 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 5BK

Altimeter-style gauge: field elevation and density altitude needles 03691215 DENSITY ALT ×1,000 FT 3,087 DENSITY ALTITUDE · FEET
field elevation density altitude

DENSITY ALTITUDE 3,087 ft

Field elevation 2,125 ft — the air behaves like 3,087 ft.

PRESSURE ALT
2,126 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

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Frequently asked questions

How high does density altitude get at 5BK in summer?

On a typical July afternoon — around 66 °F at the nearest NOAA normals station — density altitude at Black Rapids reaches roughly 3,081 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 5BK on an average day?

It swings with the seasons: from roughly −1,606 ft at the coldest month's average temperature to about 2,346 ft at the warmest month's — all from a constant field elevation of 2,125 ft. The month-by-month table above carries the full year.

What is the field elevation of Black Rapids?

2,125 ft MSL, from the FAA NASR airport record (28-day cycle effective 2026-08-06). The identifier is 5BK (FAA), in Black Rapids, Alaska.