Average Soil Temperature in Harlan, IA — September 2025
Data from Shagbark Hills (59.4 mi away) • 30 of 30 days reported
Monthly Summary by Depth
2" depth
66.8°F
avg
61.2°F – 71.2°F
30 days
4" depth
68.2°F
avg
63.3°F – 72.3°F
30 days
8" depth
69.2°F
avg
65.7°F – 72.7°F
30 days
20" depth
68°F
avg
66.2°F – 70.3°F
30 days
40" depth
66.9°F
avg
65.8°F – 68.7°F
30 days
Daily Readings
| Date | 2" | 4" | 8" | 20" | 40" |
|---|---|---|---|---|---|
| Sep 1 | 68.2°F | 69.8°F | 71.2°F | 70.3°F | 68.7°F |
| Sep 2 | 68.7°F | 70.2°F | 71.2°F | 70°F | 68.5°F |
| Sep 3 | 65.1°F | 67.3°F | 69.8°F | 69.8°F | 68.4°F |
| Sep 4 | 64.2°F | 66.2°F | 68.2°F | 68.9°F | 68.2°F |
| Sep 5 | 62.1°F | 64°F | 66.6°F | 68.2°F | 68°F |
| Sep 6 | 61.2°F | 63.3°F | 65.7°F | 67.3°F | 67.6°F |
| Sep 7 | 63°F | 64.6°F | 65.7°F | 66.4°F | 67.3°F |
| Sep 8 | 65.1°F | 66°F | 66.6°F | 66.2°F | 66.9°F |
| Sep 9 | 66.4°F | 67.5°F | 67.8°F | 66.4°F | 66.6°F |
| Sep 10 | 67.3°F | 68.7°F | 68.9°F | 66.7°F | 66.4°F |
| Sep 11 | 68.9°F | 70°F | 70°F | 67.1°F | 66.4°F |
| Sep 12 | 69.4°F | 70.3°F | 70.5°F | 67.6°F | 66.2°F |
| Sep 13 | 71.2°F | 72.3°F | 72°F | 68.2°F | 66.2°F |
| Sep 14 | 70.3°F | 71.4°F | 72°F | 68.9°F | 66.4°F |
| Sep 15 | 70.7°F | 72°F | 72.1°F | 69.1°F | 66.6°F |
| Sep 16 | 70.7°F | 72.3°F | 72.7°F | 69.4°F | 66.6°F |
| Sep 17 | 68.9°F | 70.2°F | 71.1°F | 69.4°F | 66.7°F |
| Sep 18 | 69.3°F | 70.3°F | 71.1°F | 69.1°F | 66.7°F |
| Sep 19 | 65.8°F | 67.6°F | 69.6°F | 68.9°F | 66.9°F |
| Sep 20 | 65.7°F | 67.3°F | 68.9°F | 68.4°F | 66.9°F |
| Sep 21 | 67.6°F | 68.5°F | 69.1°F | 68°F | 66.7°F |
| Sep 22 | 69.3°F | 70.3°F | 70.3°F | 68°F | 66.6°F |
| Sep 23 | 66.7°F | 68.4°F | 69.8°F | 68.4°F | 66.6°F |
| Sep 24 | 65.7°F | 67.5°F | 68.7°F | 68°F | 66.6°F |
| Sep 25 | 65.7°F | 67.1°F | 68°F | 67.6°F | 66.4°F |
| Sep 26 | 66°F | 67.5°F | 68.4°F | 67.5°F | 66.4°F |
| Sep 27 | 63.7°F | 65.7°F | 67.5°F | 67.3°F | 66.2°F |
| Sep 28 | 63.7°F | 65.1°F | 66.4°F | 66.7°F | 66.2°F |
| Sep 29 | 66.6°F | 67.6°F | 67.8°F | 66.4°F | 66°F |
| Sep 30 | 66°F | 67.3°F | 68°F | 66.7°F | 65.8°F |