Union Island weather in August 2025

Q: How hot is it in Union Island in August?

Daytime temperatures usually reach 30°C in Union Island in August with very high heat and humidity, falling to 23°C at night.

Q: How sunny is it in Union Island in August?

There are normally 8 hours of bright sunshine each day in Union Island in August - that's 62% of daylight hours.

Q: How warm is the sea around Union Island in August?

The average sea temperature around Union Island in August is 28°C.

Q: Does it rain in Union Island in August?

There are usually 20 days with some rain in Union Island in August and the average monthly rainfall is 195mm.

Q: What is the chance of a cyclone in Union Island in August?

On average less than 1 day in August in Union Island is likely to be affected by the passage of one or more tropical storms.

Expect 86°F daytime maximum temperatures in the shade with on average 8 hours of sunshine per day in Union Island in August. Check more long-term weather averages for Union Island in August before you book your next holiday to St Vincent & the Grenadines in 2025/2026.

86
86°F max day temperature
8
8 hours of sunshine per day
20
20 days with some rainfall
73
73°F min night temperature
13
13 hours of daylight per day
VH
Very High heat & humidity
7.7
7.7 inches of monthly rainfall
11
11+ (Extreme) UV index
82
82°F sea temperature

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The August weather guide for St Vincent & the Grenadines (Union Island) shows long term weather averages processed from data supplied by CRU (University of East Anglia), the Met Office & the Netherlands Meteorological Institute. Find out more about our data sources.

Metric (°C) | Imperial (°F)

More about St Vincent & the Grenadines

How hot is it in Union Island in August?

Daytime temperatures usually reach 86°F in Union Island in August with very high heat and humidity, falling to 73°F at night.

How sunny is it in Union Island in August?

There are normally 8 hours of bright sunshine each day in Union Island in August - that's 62% of daylight hours.

How warm is the sea around Union Island in August?

The average sea temperature around Union Island in August is 82°F.

Does it rain in Union Island in August?

There are usually 20 days with some rain in Union Island in August and the average monthly rainfall is 7.7 inches.

What is the chance of a hurricane in Union Island in August?

On average less than 1 day in August in Union Island is likely to be affected by the passage of one or more tropical storms.

Union Island August sunrise & sunset times

Browse the sunrise and sunset times for Union Island in August 2025. Select a month to view Union Island sunrise and sunset times for the next 12 months.

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

Date	Sunrise times	Sunset times
Friday, 1st August 2025	05:52	18:32
Saturday, 16th August 2025	05:54	18:26
Sunday, 31st August 2025	05:55	18:17

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St Vincent and the Grenadines - quick facts
Flight time^✝	11 hours
Time difference	UK -4 hours
Language(s)	English
Currency	Eastern Caribbean Dollar
Electricity	A + B + G plug (110V)
Driving side	Left
Why visit?	Beaches Nature
Tourist info	St. Vincent & the Grenadines Tourism Authority