WEATHER · CLIMATE NORMALS · 1991–2020
Houston Climate — Averages by Month
What the weather in Houston, 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 | 12.0 °C · coldest | 109.4 mm |
| February | 14.1 °C | 87.9 mm |
| March | 17.4 °C | 98.6 mm |
| April | 20.7 °C | 100.4 mm |
| May | 24.6 °C | 95.4 mm |
| June | 27.5 °C | 118.7 mm |
| July | 28.3 °C | 96.1 mm |
| August | 28.4 °C · warmest | 103.5 mm |
| September | 26.1 °C | 122.7 mm · wettest |
| October | 21.7 °C | 106.9 mm |
| November | 16.5 °C | 108.2 mm |
| December | 13.0 °C | 109.2 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 Houston — centred at 29.75°N, 95.25°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.