Houston records about 1264mm of rain across roughly 104 wet days a year, which is a 28% chance on an average day. October is the wettest month at 148mm (12% of the annual total) and February the driest at 71mm. Local rain type: thunderstorms. Houston is one of America's wettest major cities. Tropical storms and heavy thunderstorms make weather awareness essential — flash flooding is the city's biggest hazard.
Chance of rain on an average day: 28%
Rainfall climatology for Houston. The live hour-by-hour answer for today loads at the top of this page from Open-Meteo and refreshes through the day — the figures below describe a typical year, not today.
Last updated: · Live forecast data refreshes hourly.
| Annual rainfall | 1264mm |
| Rain days per year | 104 |
| Odds on an average day | 28% |
| Wettest month | October — 148mm over 12 days |
| Driest month | February — 71mm over 6 days |
| Rain type | thunderstorms |
| Best dry window | March through April offers a sweet spot of warm, less humid conditions. |
| Worst rain window | August through October brings tropical storm risk and the heaviest rainfall. |
October delivers 108% more rain than February (148mm vs 71mm). That gap is the difference between planning around showers and ignoring them.
No single month holds more than 12% of the annual total, so rain in Houston is spread through the year — there is no season you can rely on being dry.
Houston rain arrives in short, heavy bursts — shelter and timing matter more than gear.
Rain falls on about 12 days in October against 6 in February — the frequency swing matters more for planning than the millimetre totals.
Climate normals. Use them to judge whether today's live forecast at the top of the page is typical or unusual for the season.
| Month | Rainfall | Rain days | Chance on a given day | Highs |
|---|---|---|---|---|
| January | 82mm | 7 | 23% | 16°C |
| February | 71mm | 6 | 20% | 16°C |
| March | 79mm | 7 | 23% | 19°C |
| April | 81mm | 7 | 23% | 23°C |
| May | 120mm | 10 | 33% | 28°C |
| June | 148mm | 12 | 40% | 32°C |
| July | 97mm | 8 | 27% | 35°C |
| August | 101mm | 8 | 27% | 35°C |
| September | 136mm | 11 | 37% | 32°C |
| October | 148mm | 12 | 40% | 28°C |
| November | 103mm | 9 | 30% | 23°C |
| December | 91mm | 8 | 27% | 19°C |
Rain probability is the chance that at least 0.2mm falls at your location — not how long it rains. For Houston we combine the hourly probability curve, expected volume in millimetres, and the city's own rainfall record into a single umbrella verdict.
| Factor | Weight | What it measures |
|---|---|---|
| Hourly probability | 40% | Peak and sustained chance of measurable rain across the next 24 hours. |
| Expected volume | 30% | Total millimetres, which separates a passing shower from a genuine soaking. |
| Timing & duration | 20% | When rain starts, when it eases, and the longest continuous dry window. |
| Local rain type | 10% | Drizzle, brief showers, thunderstorms or monsoon — each needs different gear. |
Live hourly values come from Open-Meteo and refresh through the day. Monthly rainfall figures are climate normals, so they describe a typical year rather than a forecast.
Houston records rain on roughly 104 days a year — about a 28% chance on any given day — totalling around 1264mm.
October, with about 148mm over 12 rain days. That is 12% of the entire year's rainfall in a single month.
February is the driest month at 71mm across roughly 6 days. March through April offers a sweet spot of warm, less humid conditions.
Houston is one of America's wettest major cities. Tropical storms and heavy thunderstorms make weather awareness essential — flash flooding is the city's biggest hazard.
No. Probability is the chance that at least 0.2mm of rain falls at your location at some point in the period. Check the expected millimetres alongside it: 40% with 0.4mm is a passing shower, 40% with 12mm is a soaking.