Nahunta, Georgia · field elev 85 ft
Density Altitude at Brantley County (4J1)
Brantley County sits at 85 ft, and even a typical July afternoon (91 °F) only lifts density altitude to about 2,146 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 | 49.6 | −502 ft | 62.6 | 359 ft |
| February | 52.5 | −308 ft | 65.9 | 574 ft |
| March | 57.7 | 37 ft | 71.7 | 946 ft |
| April | 64.0 | 450 ft | 78.1 | 1,352 ft |
| May | 71.4 | 927 ft | 84.6 | 1,758 ft |
| June | 77.8 | 1,333 ft | 88.6 | 2,005 ft |
| July | 80.5 | 1,503 ft | 90.9 | 2,146 ft |
| August | 79.9 | 1,465 ft | 90.0 | 2,091 ft |
| September | 75.8 | 1,207 ft | 85.8 | 1,833 ft |
| October | 67.0 | 645 ft | 78.8 | 1,396 ft |
| November | 57.8 | 44 ft | 70.9 | 895 ft |
| December | 51.6 | −368 ft | 64.0 | 450 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 4J1
DENSITY ALTITUDE
Field elevation 85 ft — the air behaves like 2,152 ft.
- PRESSURE ALT
- 86 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 Georgia fields
- KJES — Jesup-Wayne County
Jesup · elev 108 ft
- KBQK — Brunswick Golden Isles
Brunswick · elev 26 ft
- KAYS — Waycross-Ware County
Waycross · elev 141 ft
- 3J6 — Davis Field
Folkston · elev 68 ft
- 09J — Jekyll Island
Jekyll Island · elev 11 ft
- KSSI — St Simons Island
St Simons Island · elev 19 ft
- KAMG — Bacon County
Alma · elev 200 ft
- KBHC — Baxley Municipal
Baxley · elev 201 ft
Frequently asked questions
How high does density altitude get at 4J1 in summer?
On a typical July afternoon — around 91 °F at the nearest NOAA normals station — density altitude at Brantley County reaches roughly 2,146 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 4J1 on an average day?
It swings with the seasons: from roughly −502 ft at the coldest month's average temperature to about 1,503 ft at the warmest month's — all from a constant field elevation of 85 ft. The month-by-month table above carries the full year.
What is the field elevation of Brantley County?
85 ft MSL, from the FAA NASR airport record (28-day cycle effective 2026-08-06). The identifier is 4J1 (FAA), in Nahunta, Georgia.