Which is the hottest month in Union Island?

The hottest time of year in Union Island is normally October. Expect maximum daytime temperatures to reach 30°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 207mm 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 71% 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

Q: When is the best time to visit Union Island?

The best time to visit Union Island is January, February, March, April, May and August based on the following average weather conditions. Daily hours of sunshine = 10 hours or more.

Find the best time to visit Union Island and plan your perfect trip in 2025/2026. Get holiday inspiration, weather guides, travel advice and find great deals.

Union Island by month

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

Recommended for St Vincent & the Grenadines

Sandals sale: up to £300 off Caribbean holidays

Discount Code

Save up to £300 on all inclusive holidays to the Caribbean
Discount varies by total spend. 7 night minimum stay
Travel before 31st December 2027 (inclusive)

Show discount code

******ALE

Redeem Sandals discount code >>

Expires at 23:59 on Tuesday 30th Sep 2025 · View all Sandals offers

Holiday resort finder

When is the best time to visit Union Island?

The best time to visit Union Island is 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) | Imperial (°F)