August Weather in Boise, United States

Last updated: June 24, 2025

In Boise, United States, the average temperature in August is a pleasant 26°C (78°F). However, temperatures can vary significantly, with a minimum of 9°C (48°F) and a sizzling maximum of 42°C (108°F). Expect light precipitation, averaging about 8 mm (0.3 in) over just 1 day. The humidity level rests around 50%, making it a comfortable time to explore this vibrant locale!

August Temperature in Boise

In August in Boise, the average temperature is 26°C (78°F). Maximums can reach 42°C (108°F), and minimums can drop as low as 9°C (48°F). Be prepared for a wide range of temperatures when traveling to Boise this month.

August Weather in Boise: Daily Temperature Highs, Lows, and Averages

The chart illustrates August temperature patterns in Boise, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Boise, August typically has an average temperature of 26°C (78°F), with highs reaching up to 42°C (108°F) and lows dropping to around 9°C (48°F).

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

August Precipitation in Boise

In Boise in August, the precipitation amount is 8 mm (0.3 in) over the course of 1 day.

August Precipitation Trends in Boise

The chart displays monthly precipitation patterns in Boise, 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 Boise, August typically receives around 8 mm (0.3 inches) of precipitation spread over approximately 1 days.

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

Choose your preferred precipitation unit

Millimeters (mm) Inches (in)

August Humidity in Boise

In Boise in August, humidity is 50%. With an average temperature of 26°C (78°F), this humidity feels like a warm embrace, making it pleasant for sightseeing but slightly sticky for those on the move.

August Average Humidity in Boise

This chart illustrates the average monthly humidity levels in Boise, 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 Boise is approximately 50%, 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 Boise

In Boise 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 Boise.

Maximum UV Index Levels in Boise for August

The chart shows the monthly maximum UV Index (UVI) for Boise 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 Boise typically reaches 9, which falls under the very high exposure category.

Data source: Boise 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 Boise Compares to Other Months

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

This table compares monthly weather conditions in Boise, showing how August’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	1°C (33°F)	49 mm (1.9 inches)	88%	moderate
February Weather	2°C (36°F)	50 mm (2.0 inches)	89%	moderate
March Weather	8°C (46°F)	38 mm (1.5 inches)	85%	high
April Weather	11°C (52°F)	36 mm (1.4 inches)	79%	very high
May Weather	16°C (61°F)	39 mm (1.5 inches)	71%	very high
June Weather	21°C (71°F)	21 mm (0.8 inches)	71%	extreme
July Weather	27°C (81°F)	1 mm (0.0 inches)	66%	extreme
August Weather	26°C (78°F)	8 mm (0.3 inches)	50%	very high
September Weather	20°C (68°F)	10 mm (0.4 inches)	48%	very high
October Weather	11°C (53°F)	22 mm (0.9 inches)	65%	high
November Weather	6°C (43°F)	32 mm (1.3 inches)	84%	moderate
December Weather	1°C (34°F)	40 mm (1.6 inches)	87%	low