August Weather in St. Thomas, Canada

Last updated: June 18, 2025

In St. Thomas, Canada, the average temperature in August is a pleasant 22°C (71°F). Expect minimums of 11°C (52°F) and highs of 29°C (84°F), providing a comfortable range for outdoor activities. However, be prepared for some rain, as 96 mm (3.8 in) of precipitation is expected over 11 days. With an average humidity of 80%, it's a good idea to stay hydrated and enjoy the vibrant atmosphere!

August Temperature in St. Thomas

In August in St. Thomas, the average temperature is 22°C (71°F), with maximums reaching 29°C (84°F) and minimums dropping as low as 11°C (52°F). This climate makes it an ideal time for travelers to enjoy a variety of outdoor activities in comfortably warm weather.

August Weather in St. Thomas: Daily Temperature Highs, Lows, and Averages

The chart illustrates August temperature patterns in St. Thomas, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In St. Thomas, August typically has an average temperature of 22°C (71°F), with highs reaching up to 29°C (84°F) and lows dropping to around 11°C (52°F).

Data source: Temperature data for St. Thomas generated using information from the Copernicus Climate Change Service.

August Precipitation in St. Thomas

In St. Thomas in August, the precipitation amount is 96 mm (3.8 in) spread over 11 days, resulting in a significant accumulation of rainfall.

August Precipitation Trends in St. Thomas

The chart displays monthly precipitation patterns in St. Thomas, with values for each month alongside August’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how August’s conditions compare to those of other months. In St. Thomas, August typically receives around 96 mm (3.8 inches) of precipitation spread over approximately 11 days.

Data source: Precipitation data for August generated using information from the Copernicus Climate Change Service.

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Millimeters (mm) Inches (in)

August Humidity in St. Thomas

In St. Thomas in August, humidity is 80%. With an average temperature of 22°C (71°F), this humidity feels like a warm, enveloping blanket, making travel slightly uncomfortable as skin becomes clammy and sweat clings to clothes.

August Average Humidity in St. Thomas

This chart illustrates the average monthly humidity levels in St. Thomas, with August’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In August, average humidity in St. Thomas is approximately 80%, offering insight into how humid the weather typically is during this month.

Data source: Humidity data for August generated using information from the Copernicus Climate Change Service.

August UV Index in St. Thomas

In St. Thomas in August, the maximum UV index is 9, which corresponds to a very high Exposure Category. The time to burn is just 15 minutes, so it's essential to take precautions. For detailed information, you can check the Hourly UV Index in St. Thomas.

Maximum UV Index Levels in St. Thomas for August

The chart shows the monthly maximum UV Index (UVI) for St. Thomas in August, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In August, the maximum UV index in St. Thomas typically reaches 9, which falls under the very high exposure category.

Data source: St. Thomas August UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

Extreme (11+): Avoid the sun, stay in shade.
Very High (8-10): Limit sun exposure.
High (6-7): Use SPF 30+ and protective clothing.
Moderate (3-5): Midday shade recommended.
Low (0-2): No protection needed.

How August Weather in St. Thomas Compares to Other Months

Weather in St. Thomas varies notably across the year, with each month offering distinct climate conditions. This page compares August’s weather to other months in St. Thomas, focusing on differences in temperature, rainfall, humidity, and UV levels.

This table compares monthly weather conditions in St. Thomas, showing how August’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-3°C (27°F)	76 mm (3.0 inches)	90%	moderate
February Weather	-3°C (27°F)	79 mm (3.1 inches)	90%	moderate
March Weather	1°C (34°F)	81 mm (3.2 inches)	87%	moderate
April Weather	6°C (43°F)	106 mm (4.2 inches)	87%	very high
May Weather	13°C (55°F)	99 mm (3.9 inches)	82%	very high
June Weather	19°C (66°F)	93 mm (3.7 inches)	81%	very high
July Weather	22°C (72°F)	91 mm (3.6 inches)	79%	very high
August Weather	22°C (71°F)	96 mm (3.8 inches)	80%	very high
September Weather	18°C (65°F)	82 mm (3.2 inches)	81%	very high
October Weather	12°C (55°F)	123 mm (4.9 inches)	84%	high
November Weather	5°C (41°F)	94 mm (3.7 inches)	88%	moderate
December Weather	1°C (34°F)	77 mm (3.0 inches)	87%	low