Which is the hottest month in Union Island?

The hottest time of year in Union Island is normally September. Expect maximum daytime temperatures to reach 29°C with very high heat and humidity.

Which month has the most rain in Union Island?

In terms of rainfall, October is usually the wettest month in Union Island with 309mm on average. There are normally 18 days in October with some rain.

When is it sunniest in Union Island?

The sunniest time of year in Union Island is normally February with bright sunshine on average for 72% of daylight hours; that's 8 hours of sunshine per day.

When is the sea warmest in Union Island?

The sea is usually at its warmest in Union Island in September when the water temperature reaches 29°C.

Best time to visit Union Island

The best times to visit Union Island, St Vincent & the Grenadines are in January, February, March, April, May and August based on our default weather conditions. Update your weather preferences to see which months best match.

Union Island by month

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

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When is the best time to visit Union Island?

The best times to visit Union Island, St Vincent & the Grenadines are in January, February, March, April, May and August based on the following average weather conditions.

Daily hours of sunshine = 10 hours or more [remove]

Change the criteria to reflect your weather preferences.

4
Jan
4
Feb
4
Mar
4
Apr
4
May
3
Jun
3
Jul
4
Aug
3
Sep
3
Oct
3
Nov
3
Dec

Change criteria

Hours of Sunshine (daily)

8
Jan
8
Feb
8
Mar
8
Apr
8
May
7
Jun
7
Jul
8
Aug
7
Sep
7
Oct
7
Nov
7
Dec

Best time to visit

Destination

Daytime temperature

Sunshine hours

Sea temperature

Monthly rainfall

Days with some rain

Heat & humidity

The weather guide for St Vincent & the Grenadines (Union Island) shows long term weather averages processed from data supplied by CRU (University of East Anglia) & today's weather forecast provided by meteoblue. Find out more about our data sources.

Metric (°C / mm) | Imperial (°F / inches)