San Andrés records about 1520mm of rain across roughly 98 wet days a year, which is a 27% chance on an average day. October is the wettest month at 242mm (16% of the annual total) and March the driest at 12mm. Local rain type: brief showers. San Andrés has a Caribbean wet season (September-December). The island's "sea of seven colors" is most vivid on sunny days — plan snorkeling for dry months.
Chance of rain on an average day: 27%
Rainfall climatology for San Andrés. 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 | 1520mm |
| Rain days per year | 98 |
| Odds on an average day | 27% |
| Wettest month | October — 242mm over 18 days |
| Driest month | March — 12mm over 1 days |
| Rain type | brief showers |
| Best dry window | January through April offers the driest conditions for diving and beach activities. |
| Worst rain window | October and November bring the heaviest Caribbean rain. |
October delivers 1917% more rain than March (242mm vs 12mm). 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 San Andrés is spread through the year — there is no season you can rely on being dry.
San Andrés rain typically comes as discrete showers, so a compact umbrella and a flexible plan are usually enough.
Rain falls on about 18 days in October against 1 in March — 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 | 32mm | 2 | 7% | 29°C |
| February | 18mm | 1 | 3% | 29°C |
| March | 12mm | 1 | 3% | 29°C |
| April | 35mm | 3 | 10% | 30°C |
| May | 88mm | 6 | 20% | 30°C |
| June | 142mm | 10 | 33% | 31°C |
| July | 108mm | 8 | 27% | 31°C |
| August | 125mm | 9 | 30% | 31°C |
| September | 178mm | 13 | 43% | 31°C |
| October | 242mm | 18 | 60% | 30°C |
| November | 222mm | 16 | 53% | 30°C |
| December | 125mm | 9 | 30% | 29°C |
Rain probability is the chance that at least 0.2mm falls at your location — not how long it rains. For San Andrés 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.
San Andrés records rain on roughly 98 days a year — about a 27% chance on any given day — totalling around 1520mm.
October, with about 242mm over 18 rain days. That is 16% of the entire year's rainfall in a single month.
March is the driest month at 12mm across roughly 1 days. January through April offers the driest conditions for diving and beach activities.
San Andrés has a Caribbean wet season (September-December). The island's "sea of seven colors" is most vivid on sunny days — plan snorkeling for dry months.
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.