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 a pleasant month, with temperature in the range of an average low of 46.6°F (8.1°C) and an average high of 71.6°F (22°C).

Temperature

In Boise, the average high-temperature in May rises, from an enjoyable 62.2°F (16.8°C) in April, to a pleasant 71.6°F (22°C). In Boise, the average low-temperature is 46.6°F (8.1°C).

Humidity

In May, the average relative humidity is 48.7%.

Rainfall

In Boise, during May, the rain falls for 7.7 days and regularly aggregates up to 1.4" (35.3mm) of precipitation. In Boise, during the entire year, the rain falls for 87.6 days and collects up to 11.7" (297.9mm) of precipitation.

Snowfall

May through September are months without snowfall.

Daylight

In Boise, the average length of the day is 14.7h.

Sunshine

In May, the average sunshine is 10.8h.

UV index

In Boise, the average daily maximum UV index is 7. A UV Index estimate of 6 to 7 represents a high health vulnerability from the exposure to the Sun's UV radiation for average individuals.
Note: In May, the average maximum UV index of 7 translate into the following recommendations:
Take precautions and adopt sun safety practices. Protection against sunburn is obliged. Seek shade and minimize exposure to direct Sun in a period between 10 a.m. and 4 p.m. when UV radiation is most intense; keep in mind that shade structures like parasols or canopies do not provide perfect sun protection. Sun-protective clothing, a long-sleeved shirt and pants, a wide-brimmed hat, and UVA and UVB-blocking sunglasses are particularly helpful in blocking UV radiation's harmful effects.

What is the temperature in May in Boise?

In May, in Boise, Idaho, the average high-temperature is 71.6°F (22°C), and the average low-temperature is 46.6°F (8.1°C).

What is the average humidity in May in Boise?

In May, the average relative humidity in Boise is 48.7%.

How much does it rain in Boise in May?

In Boise, Idaho, in May, it is raining for 7.7 days, with typically 1.4" (35.3mm) of accumulated precipitation.

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 September are months without snowfall in Boise.

What is the average length of the day in May in Boise?

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

How long on average sun shines in May in Boise?

In Boise, the average sunshine in May is 10.8h.

How high is the UV index in May in Boise?

In May, the average daily maximum UV index in Boise is 7. A UV Index reading of 6 to 7 represents a high health risk from unsafe exposure to the Sun's UV rays.
Average temperature in May - Boise, ID
  • Average high temperature in May: 71.6°F

The warmest month (with the highest average high temperature) is July (91.2°F).
The month with the lowest average high temperature is December (37.5°F).

  • Average low temperature in May: 46.5°F

The month with the highest average low temperature is July (60.4°F).
The coldest month (with the lowest average low temperature) is December (24°F).

Average humidity in May - Boise, ID
  • Average humidity in May: 48.7%

The month with the highest relative humidity is January (75%).
The month with the lowest relative humidity is July (36.1%).

Average rainfall in May - Boise, ID
  • Average rainfall in May: 1.4"

The wettest month (with the highest rainfall) is December (1.6").
The driest month (with the lowest rainfall) is August (0.2").

Average rainfall days in May - Boise, ID
  • Average rainfall days in May: 7.7 days

The month with the highest number of rainy days is December (11.8 days).
The month with the lowest number of rainy days is August (2.4 days).

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

The month with the highest snowfall is December (7").
Months with the lowest snowfall are May, June, July, August and September (0").

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

The month with the highest number of snowfall days is December (6 days).
Months with the lowest number of snowfall days are May, 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: 10.8h

The month with most sunshine is July (Average sunshine: 12.9h).
The month with least sunshine is December (Average sunshine: 3.4h).

Average UV index in May - Boise, ID
  • Average UV index in May: 7

Months with the highest UV index are June and July (UV index 9).
Months with the lowest UV index are January and December (UV index 1).