Derby, IA
Climate overview — based on NOAA 1991-2020 normals from CHARITON 1 E, IA US.
Year-round temperatures (°F)
Climate summary
Derby has an annual average temperature of 48.3°F with about 37.3 inches of precipitation per year and 24.1 inches of snow. The warmest month is July (average high 84.5°F), and the coldest is January (average low 10.6°F). May is typically the wettest month (5.39 in) and January the driest (0.96 in). Snow typically falls from October through April.
Best time to visit Derby
Full guide →Climate change signal
All-time records →26 of 366 (7.1%) of Derby's all-time daily heat records have been set since 2015. If records were spread evenly across the station's history, only about 5% would fall in any given decade.
| 1890s | 5 | |
| 1900s | 17 | |
| 1910s | 27 | |
| 1920s | 18 | |
| 1930s | 103 | |
| 1940s | 19 | |
| 1950s | 39 | |
| 1960s | 20 | |
| 1970s | 12 | |
| 1980s | 30 | |
| 1990s | 19 | |
| 2000s | 16 | |
| 2010s | 27 | |
| 2020s | 14 |
Bars: number of all-time daily heat records still standing that were set in each decade.
Monthly averages
| Month | Avg High | Avg Low | Avg Temp | Precipitation | Snow | Rainy days |
|---|---|---|---|---|---|---|
| January | 31.0°F | 10.6°F | 20.8°F | 0.96 in | 7.9 in | 7 |
| February | 35.7°F | 13.7°F | 24.7°F | 1.40 in | 6.5 in | 8 |
| March | 48.5°F | 24.7°F | 36.6°F | 1.90 in | 3.5 in | 9 |
| April | 61.0°F | 35.0°F | 48.0°F | 4.15 in | 0.8 in | 12 |
| May | 70.7°F | 46.6°F | 58.7°F | 5.39 in | — | 15 |
| June | 80.3°F | 57.1°F | 68.7°F | 4.92 in | — | 12 |
| July | 84.5°F | 61.5°F | 73.0°F | 4.21 in | — | 10 |
| August | 83.1°F | 59.0°F | 71.1°F | 4.40 in | — | 11 |
| September | 76.1°F | 49.8°F | 62.9°F | 3.71 in | — | 9 |
| October | 63.8°F | 37.8°F | 50.8°F | 2.98 in | 0.3 in | 9 |
| November | 48.6°F | 26.1°F | 37.4°F | 2.03 in | 2.0 in | 7 |
| December | 36.5°F | 16.2°F | 26.4°F | 1.27 in | 3.1 in | 8 |
Climate twins of Derby
Why these? →The most climatically similar US cities at least 140 miles away (by monthly temperature + precipitation pattern).