Morris, Illinois · field elev 585 ft
Density Altitude at Morris Municipal/James R Washburn Field (C09)
Morris Municipal/James R Washburn Field sits at 585 ft, and even a typical July afternoon (85 °F) only lifts density altitude to about 2,387 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 | 23.4 | −1,697 ft | 31.2 | −1,144 ft |
| February | 27.4 | −1,412 ft | 35.6 | −837 ft |
| March | 38.3 | −651 ft | 47.7 | −10 ft |
| April | 50.3 | 164 ft | 60.9 | 865 ft |
| May | 61.6 | 910 ft | 72.1 | 1,586 ft |
| June | 71.4 | 1,541 ft | 81.7 | 2,189 ft |
| July | 75.0 | 1,769 ft | 84.9 | 2,387 ft |
| August | 72.8 | 1,630 ft | 82.7 | 2,251 ft |
| September | 66.1 | 1,202 ft | 77.4 | 1,920 ft |
| October | 53.6 | 384 ft | 64.4 | 1,092 ft |
| November | 40.3 | −513 ft | 49.0 | 77 ft |
| December | 29.1 | −1,292 ft | 36.7 | −761 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 C09
DENSITY ALTITUDE
Field elevation 585 ft — the air behaves like 2,393 ft.
- PRESSURE ALT
- 586 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 Illinois fields
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Joliet · elev 582 ft
- 8N2 — Skydive Chicago
Ottawa · elev 616 ft
- KDTG — Dwight
Dwight · elev 632 ft
- KLOT — Lewis University
Chicago/Romeoville · elev 679 ft
- 1C5 — Bolingbrook'S Clow International
Bolingbrook · elev 675 ft
- KARR — Aurora Municipal
Chicago/Aurora · elev 712 ft
- 0C2 — Hinckley
Hinckley · elev 760 ft
Frequently asked questions
How high does density altitude get at C09 in summer?
On a typical July afternoon — around 85 °F at the nearest NOAA normals station — density altitude at Morris Municipal/James R Washburn Field reaches roughly 2,387 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 C09 on an average day?
It swings with the seasons: from roughly −1,697 ft at the coldest month's average temperature to about 1,769 ft at the warmest month's — all from a constant field elevation of 585 ft. The month-by-month table above carries the full year.
What is the field elevation of Morris Municipal/James R Washburn Field?
585 ft MSL, from the FAA NASR airport record (28-day cycle effective 2026-08-06). The identifier is C09 (FAA), in Morris, Illinois.