Greybull, Wyoming · field elev 3,942 ft
Density Altitude at South Big Horn County (KGEY)
From a field elevation of 3,942 ft, a typical July afternoon at South Big Horn County (91 °F) raises density altitude to about 6,857 ft — solidly into the range where performance charts deserve a close read.
Typical density altitude by month
| Month | Avg temp °F | DA at avg temp | Afternoon high °F | DA on a typical afternoon |
|---|---|---|---|---|
| January | 17.5 | 2,090 ft | 28.9 | 2,883 ft |
| February | 23.6 | 2,518 ft | 35.5 | 3,332 ft |
| March | 37.9 | 3,493 ft | 51.2 | 4,370 ft |
| April | 46.7 | 4,076 ft | 60.0 | 4,935 ft |
| May | 57.0 | 4,743 ft | 70.4 | 5,587 ft ▲ |
| June | 67.0 | 5,375 ft | 81.4 | 6,260 ft ▲ |
| July | 74.9 | 5,864 ft | 91.4 | 6,857 ft ▲ |
| August | 72.3 | 5,704 ft | 88.8 | 6,703 ft ▲ |
| September | 60.9 | 4,992 ft | 76.7 | 5,975 ft ▲ |
| October | 46.5 | 4,063 ft | 59.9 | 4,928 ft |
| November | 31.2 | 3,040 ft | 43.5 | 3,866 ft |
| December | 19.3 | 2,217 ft | 30.8 | 3,013 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 KGEY
DENSITY ALTITUDE caution
Field elevation 3,942 ft — the air behaves like 6,834 ft.
- PRESSURE ALT
- 3,944 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 Wyoming fields
- U68 — North Big Horn County
Cowley/Lovell/Byron · elev 4,094 ft
- KWRL — Worland Municipal
Worland · elev 4,252 ft
- KPOY — Powell Municipal
Powell · elev 5,096 ft
- KCOD — Yellowstone Regional
Cody · elev 5,102 ft
- KSHR — Sheridan County
Sheridan · elev 4,021 ft
- KHSG — Hot Springs County
Thermopolis · elev 4,892 ft
- KBYG — Johnson County
Buffalo · elev 4,970 ft
- 49U — Shoshoni Municipal
Shoshoni · elev 4,818 ft
Frequently asked questions
How high does density altitude get at KGEY in summer?
On a typical July afternoon — around 91 °F at the nearest NOAA normals station — density altitude at South Big Horn County reaches roughly 6,857 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 KGEY on an average day?
It swings with the seasons: from roughly 2,090 ft at the coldest month's average temperature to about 5,864 ft at the warmest month's — all from a constant field elevation of 3,942 ft. The month-by-month table above carries the full year.
What is the field elevation of South Big Horn County?
3,942 ft MSL, from the FAA NASR airport record (28-day cycle effective 2026-08-06). The identifier is KGEY (ICAO) / GEY (FAA), in Greybull, Wyoming.