Boise
Idaho, USA
Long-term weather forecast
Long-term weather forecast

May weather forecast and climate
Boise, ID

The golden fall season in Boise, Idaho, with the tall city buildings
The golden fall season in Boise, Idaho, with the tall city buildings
May, the last month of the spring, in Boise, is an enjoyable month, with average temperature ranging between max 67.1°F (19.5°C) and min 45.1°F (7.3°C).

Temperature

In Boise, the average high-temperature in May rises, from a mild 56.7°F (13.7°C) in April, to a comfortable 67.1°F (19.5°C). In Boise, the average low-temperature is 45.1°F (7.3°C).

Humidity

In Boise, the average relative humidity is 51%.

Rainfall

In Boise, it is raining for 11.1 days, with typically 1.46" (37mm) of accumulated precipitation. Throughout the year, in Boise, Idaho, there are 116.8 rainfall days, and 15.08" (383mm) of precipitation is accumulated.

Snowfall

In Boise snow does not fall through October.

Daylight

The average length of the day in May is 14.7h.

Sunshine

The average sunshine in Boise, Idaho, is 10.9h.

UV index

In May, the average daily maximum UV index in Boise is 5. A UV Index of 3 to 5 symbolizes a moderate threat to health from the exposure to the Sun's UV rays for average individuals.
Note: In May, the average maximum UV index of 5 translate into the following recommendations:
Take precautions. Light skin individuals may get burned in less than 30 minutes. The Sun's most intense and consequently most harmful UV radiation during midday hours should be decreased by minimizing exposure and seeking shade. A wide-brim hat offers excellent sun protection for eyes, ears, face, and neck. Sunglasses with UVA and UVB protection significantly reduce eye damage from sun exposure. Tightly woven, loose-fitting clothes provide additional protection from the Sun. Caution! The reflection of snow can nearly double the intensity of the Sun's UV radiation.

What is the temperature in May in Boise?

In Boise, in May, the average high-temperature is 67.1°F (19.5°C), and the average low-temperature is 45.1°F (7.3°C).

What is the average humidity in May in Boise?

In Boise, the average relative humidity in May is 51%.

How much does it rain in Boise in May?

In Boise, in May, during 11.1 rainfall days, 1.46" (37mm) of precipitation is typically accumulated.

Does it snow in Boise in May?

In May, in Boise, Idaho, it doesn't snow. April is the latest month when it typically snows.

When it does not snow in Boise?

May through October are months without snowfall in Boise.

How many hours of daylight does Boise have in May?

The average length of the day in May in Boise is 14.7h.

How many hours of sunshine does Boise have in May?

In Boise, Idaho, the average sunshine in May is 10.9h.

What is the UV index intensity in May in Boise?

The average daily maximum UV index in May in Boise is 5. A UV Index estimate of 3 to 5 represents a medium hazard to health from the exposure to the Sun's UV radiation.
Average temperature in May - Boise, ID
  • Average high temperature in May: 19.5°C

The warmest month (with the highest average high temperature) is July (31°C).
The month with the lowest average high temperature is December (1.5°C).

  • Average low temperature in May: 7.3°C

The month with the highest average low temperature is August (16.3°C).
The coldest month (with the lowest average low temperature) is December (-4.9°C).

Average humidity in May - Boise, ID
  • Average humidity in May: 51%

The month with the highest relative humidity is January (80%).
The month with the lowest relative humidity is July (30%).

Average rainfall in May - Boise, ID
  • Average rainfall in May: 37mm

The wettest month (with the highest rainfall) is March (56mm).
The driest month (with the lowest rainfall) is July (5mm).

Average rainfall days in May - Boise, ID
  • Average rainfall days in May: 11.1 days

The month with the highest number of rainy days is March (16.2 days).
The month with the lowest number of rainy days is July (4.5 days).

Average snowfall in May - Boise, ID
  • Average snowfall in May: 0mm

The month with the highest snowfall is December (169mm).
Months with the lowest snowfall are May, June, July, August, September and October (0mm).

Average snowfall days in May - Boise, ID
  • Average snowfall days in May: 0.1 days

The month with the highest number of snowfall days is December (9.2 days).
Months with the lowest number of snowfall days are June, July, August and September (0 days).

Average daylight in May / Average sunshine in May - Boise, ID
  • Average daylight in May: 14.7h

The month with the longest days is June (Average daylight: 15.4h).
The month with shortest days is December (Average daylight: 9h).

  • Average sunshine in May: 10.9h

The month with most sunshine is July (Average sunshine: 12.1h).
The month with least sunshine is December (Average sunshine: 5.5h).

Average UV index in May - Boise, ID
  • Average UV index in May: 5

The month with the highest UV index is July (UV index 7).
Months with the lowest UV index are January, February, November and December (UV index 2).