Mount Cook records about 4900mm of rain across roughly 200 wet days a year, which is a 55% chance on an average day. May is the wettest month at 480mm (10% of the annual total) and February the driest at 340mm. Local rain type: steady rain. Mount Cook is one of the wettest places in New Zealand — up to 5 meters of rain annually. Full alpine waterproof gear is essential. Clear days are precious and should be seized immediately.
Chance of rain on an average day: 55%
Rainfall climatology for Mount Cook. 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 | 4900mm |
| Rain days per year | 200 |
| Odds on an average day | 55% |
| Wettest month | May — 480mm over 20 days |
| Driest month | February — 340mm over 14 days |
| Rain type | steady rain |
| Best dry window | January and February offer the most frequent clear spells, though rain remains possible on any day. |
| Worst rain window | May brings the heaviest precipitation — often falling as snow above 1,500m. Multi-day rain events lasting 3-4 days are common. |
May delivers 41% more rain than February (480mm vs 340mm). That gap is the difference between planning around showers and ignoring them.
No single month holds more than 10% of the annual total, so rain in Mount Cook is spread through the year — there is no season you can rely on being dry.
Mount Cook rain typically comes as discrete showers, so a compact umbrella and a flexible plan are usually enough.
Rain falls on about 20 days in May against 14 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 | 380mm | 16 | 53% | 20°C |
| February | 340mm | 14 | 47% | 20°C |
| March | 400mm | 16 | 53% | 18°C |
| April | 420mm | 17 | 57% | 16°C |
| May | 480mm | 20 | 67% | 12°C |
| June | 450mm | 19 | 63% | 10°C |
| July | 410mm | 17 | 57% | 8°C |
| August | 380mm | 16 | 53% | 8°C |
| September | 370mm | 15 | 50% | 10°C |
| October | 420mm | 17 | 57% | 12°C |
| November | 430mm | 18 | 60% | 16°C |
| December | 380mm | 16 | 53% | 18°C |
Rain probability is the chance that at least 0.2mm falls at your location — not how long it rains. For Mount Cook 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.
Mount Cook records rain on roughly 200 days a year — about a 55% chance on any given day — totalling around 4900mm.
May, with about 480mm over 20 rain days. That is 10% of the entire year's rainfall in a single month.
February is the driest month at 340mm across roughly 14 days. January and February offer the most frequent clear spells, though rain remains possible on any day.
Mount Cook is one of the wettest places in New Zealand — up to 5 meters of rain annually. Full alpine waterproof gear is essential. Clear days are precious and should be seized immediately.
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.