Keystone Heights, Florida · field elev 196 ft
Density Altitude at Keystone Heights (42J)
Keystone Heights sits at 196 ft, and even a typical July afternoon (92 °F) only lifts density altitude to about 2,373 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 | 56.8 | 115 ft | 68.3 | 865 ft |
| February | 59.2 | 273 ft | 71.1 | 1,044 ft |
| March | 64.2 | 600 ft | 76.3 | 1,375 ft |
| April | 69.9 | 968 ft | 81.9 | 1,726 ft |
| May | 76.5 | 1,387 ft | 87.4 | 2,067 ft |
| June | 82.1 | 1,738 ft | 91.8 | 2,336 ft |
| July | 83.3 | 1,813 ft | 92.4 | 2,373 ft |
| August | 82.9 | 1,788 ft | 92.0 | 2,348 ft |
| September | 80.2 | 1,620 ft | 89.1 | 2,171 ft |
| October | 72.7 | 1,147 ft | 83.0 | 1,795 ft |
| November | 64.5 | 619 ft | 76.3 | 1,375 ft |
| December | 59.0 | 260 ft | 70.9 | 1,032 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 42J
DENSITY ALTITUDE
Field elevation 196 ft — the air behaves like 2,348 ft.
- PRESSURE ALT
- 197 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 Florida fields
- KGNV — Gainesville Regional
Gainesville · elev 151 ft
- 28J — Palatka Municipal/Lt Kay Larkin Field
Palatka · elev 48 ft
- KVQQ — Cecil
Jacksonville · elev 80 ft
- 0J8 — Flying Ten
Archer · elev 92 ft
- KHEG — Herlong Recreational
Jacksonville · elev 86 ft
- 6J8 — Oak Tree Landing
High Springs · elev 90 ft
- KLCQ — Lake City Gateway
Lake City · elev 201 ft
- X60 — Williston Regional
Williston · elev 76 ft
Frequently asked questions
How high does density altitude get at 42J in summer?
On a typical July afternoon — around 92 °F at the nearest NOAA normals station — density altitude at Keystone Heights reaches roughly 2,373 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 42J on an average day?
It swings with the seasons: from roughly 115 ft at the coldest month's average temperature to about 1,813 ft at the warmest month's — all from a constant field elevation of 196 ft. The month-by-month table above carries the full year.
What is the field elevation of Keystone Heights?
196 ft MSL, from the FAA NASR airport record (28-day cycle effective 2026-08-06). The identifier is 42J (FAA), in Keystone Heights, Florida.