WEATHER · CLIMATE NORMALS · 1991–2020
Omaha Climate — Averages by Month
What the weather in Omaha, USaverages across a standard 30-year period. Each month's figure is the 1991–2020 mean temperature and total rainfall from the ERA5 reanalysis — the long-run normal a place settles around, not a forecast for any particular day.
Month-by-month normals
| Month | Avg temperature | Avg rainfall |
|---|---|---|
| January | -4.6 °C · coldest | 28.3 mm |
| February | -2.3 °C | 35.6 mm |
| March | 4.4 °C | 63.1 mm |
| April | 10.9 °C | 106.2 mm |
| May | 17.1 °C | 142.9 mm · wettest |
| June | 22.7 °C | 133.8 mm |
| July | 24.9 °C · warmest | 90.9 mm |
| August | 23.6 °C | 92.6 mm |
| September | 19.2 °C | 79.3 mm |
| October | 12.0 °C | 70.1 mm |
| November | 4.2 °C | 46.2 mm |
| December | -2.2 °C | 39.1 mm |
How to read these numbers
These are reanalysis normals, not readings from a single weather station. They come from the ERA5 0.25° (~25 km) global reanalysis grid, sampled at the grid cell nearest Omaha — centred at 41.25°N, 96.00°W. A reanalysis blends observations with a physics model onto an even grid, so a coastal or mountain city's cell can read a little cooler, warmer, wetter or drier than the city centre itself. The month-to-month shape — when it's hot, when it rains — is what these normals capture best.
“Normal” means the 1991–2020 average, the current World Meteorological Organization standard period. A normal is what a place tends toward over decades — any single day, month or year can and will depart from it.