2025 Compare Climate & Weather:
Johnstown, CO vs Boise City, ID

Highlights

On average, there are 206 sunny days per year in Boise City. Johnstown averages 239 sunny days per year. The US average is 205 sunny days.

Boise City, Idaho gets 13 inches of rain, on average, per year. Johnstown, Colorado gets 14.9 inches of rain, on average, per year. The US average is 38.1 inches of rain per year.

Boise City averages 17.5 inches of snow per year. Johnstown averages 38 inches of snow per year. The US average is 27.8 inches of snow per year.

Weather Highlights

Boise City, Idaho
Summer High: the July high is around 91.6 degrees
Winter Low: the January low is 23.7
Rain: averages 13 inches of rain a year
Snow: averages 17.5 inches of snow a year

Johnstown, Colorado
Summer High: the July high is around 90.4 degrees
Winter Low: the January low is 13.5
Rain: averages 14.9 inches of rain a year
Snow: averages 38 inches of snow a year

BestPlaces Comfort Index

The annual BestPlaces Comfort Index for Boise is 7.3 (10=best), which means it is one of the most pleasant places in Idaho.

The annual BestPlaces Comfort Index for Johnstown is 7.2 (10=best), which means it is more comfortable than most places in Colorado.

Today's Weather - Johnstown, CO

62°F

Today's Weather - Boise City, ID

66°F

Average Monthly High / Low (°F)

Hot, Freezing, Rainy, Snowy Days: Johnstown / Boise City

July is the hottest month for Johnstown with an average high temperature of 90.4°, which ranks it as warmer than most places in Colorado. In Johnstown, there are 3 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Johnstown are September, May and June.

July is the hottest month for Boise with an average high temperature of 91.6°, which ranks it as one of the hottest places in Idaho. In Boise, there are 3 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Boise are September, June and May.

December has the coldest nighttime temperatures for Johnstown with an average of 13.2°. This is about average compared to other places in Colorado.

December has the coldest nighttime temperatures for Boise with an average of 22.7°. This is warmer than most places in Idaho.

In Johnstown, there are 46.3 days annually when the high temperature is over 90°, which is hotter than most places in Colorado.

In Boise, there are 51.0 days annually when the high temperature is over 90°, which is one of the hottest places in Idaho.

In Johnstown, there are 172.8 days annually when the nighttime low temperature falls below freezing, which is about average compared to other places in Colorado.

In Boise, there are 114.9 days annually when the nighttime low temperature falls below freezing, which is one of the warmest places in Idaho.

In Johnstown, there are 9.9 days annually when the nighttime low temperature falls below zero°, which is colder than most places in Colorado.

In Boise, there are 2.8 days annually when the nighttime low temperature falls below zero°, which is warmer than most places in Idaho.

May is the wettest month in Johnstown with 2.3 inches of rain, and the driest month is February with 0.4 inches. The wettest season is Summer with 38% of yearly precipitation and 10% occurs in Spring, which is the driest season. The annual rainfall of 14.9 inches in Johnstown means that it is drier than most places in Colorado.


December is the wettest month in Boise with 1.9 inches of rain, and the driest month is July with 0.3 inches. The wettest season is Spring with 35% of yearly precipitation and 10% occurs in Autumn, which is the driest season. The annual rainfall of 13.0 inches in Boise means that it is about average compared to other places in Idaho.

May is the rainiest month in Johnstown with 10.5 days of rain, and January is the driest month with only 4.3 rainy days. There are 80.9 rainy days annually in Johnstown, which is about average compared to other places in Colorado. The rainiest season is Summer when it rains 31% of the time and the driest is Spring with only a 17% chance of a rainy day.

December is the rainiest month in Boise with 11.3 days of rain, and August is the driest month with only 2.3 rainy days. There are 87.0 rainy days annually in Boise, which is less rainy than most places in Idaho. The rainiest season is Spring when it rains 35% of the time and the driest is Autumn with only a 12% chance of a rainy day.

An annual snowfall of 38.0 inches in Johnstown means that it is less snowy than most places in Colorado.

An annual snowfall of 17.5 inches in Boise means that it is less snowy than most places in Idaho.

March is the snowiest month in Johnstown with 7.7 inches of snow, and 7 months of the year have significant snowfall.

December is the snowiest month in Boise with 6.4 inches of snow, and 5 months of the year have significant snowfall.