Denver records about 382mm of rain across roughly 82 wet days a year, which is a 22% chance on an average day. May is the wettest month at 62mm (16% of the annual total) and January the driest at 13mm. Local rain type: brief showers. Denver is surprisingly dry for a mountain city. Summer afternoon thunderstorms are brief and dramatic — they build over the Rockies and sweep across the city.
Chance of rain on an average day: 22%
Rainfall climatology for Denver. 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 | 382mm |
| Rain days per year | 82 |
| Odds on an average day | 22% |
| Wettest month | May — 62mm over 13 days |
| Driest month | January — 13mm over 3 days |
| Rain type | brief showers |
| Best dry window | September through November offers warm, dry "Indian summer" conditions. |
| Worst rain window | May and June bring the most rainfall as spring storms, often with impressive hail. |
May delivers 377% more rain than January (62mm vs 13mm). That gap is the difference between planning around showers and ignoring them.
No single month holds more than 16% of the annual total, so rain in Denver is spread through the year — there is no season you can rely on being dry.
Denver rain typically comes as discrete showers, so a compact umbrella and a flexible plan are usually enough.
Rain falls on about 13 days in May against 3 in January — 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 | 13mm | 3 | 10% | 6°C |
| February | 13mm | 3 | 10% | 6°C |
| March | 33mm | 7 | 23% | 10°C |
| April | 44mm | 9 | 30% | 16°C |
| May | 62mm | 13 | 43% | 22°C |
| June | 48mm | 10 | 33% | 28°C |
| July | 48mm | 10 | 33% | 32°C |
| August | 46mm | 9 | 30% | 32°C |
| September | 30mm | 6 | 20% | 28°C |
| October | 27mm | 6 | 20% | 22°C |
| November | 21mm | 4 | 13% | 16°C |
| December | 14mm | 3 | 10% | 10°C |
Rain probability is the chance that at least 0.2mm falls at your location — not how long it rains. For Denver 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.
Denver records rain on roughly 82 days a year — about a 22% chance on any given day — totalling around 382mm.
May, with about 62mm over 13 rain days. That is 16% of the entire year's rainfall in a single month.
January is the driest month at 13mm across roughly 3 days. September through November offers warm, dry "Indian summer" conditions.
Denver is surprisingly dry for a mountain city. Summer afternoon thunderstorms are brief and dramatic — they build over the Rockies and sweep across the city.
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.