2025 Compare Climate & Weather:
Sundance, WY vs Castle Rock, CO

Highlights

On average, there are 243 sunny days per year in Castle Rock. Sundance averages 226 sunny days per year. The US average is 205 sunny days.

Castle Rock, Colorado gets 18.6 inches of rain, on average, per year. Sundance, Wyoming gets 21.6 inches of rain, on average, per year. The US average is 38.1 inches of rain per year.

Castle Rock averages 78.3 inches of snow per year. Sundance averages 113 inches of snow per year. The US average is 27.8 inches of snow per year.

Weather Highlights

Castle Rock, Colorado
Summer High: the July high is around 85.5 degrees
Winter Low: the January low is 18.6
Rain: averages 18.6 inches of rain a year
Snow: averages 78.3 inches of snow a year

Sundance, Wyoming
Summer High: the July high is around 81.2 degrees
Winter Low: the January low is 12.4
Rain: averages 21.6 inches of rain a year
Snow: averages 113 inches of snow a year

BestPlaces Comfort Index

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

The annual BestPlaces Comfort Index for Sundance is 6.3 (10=best), which means it is less comfortable than most places in Wyoming.

Today's Weather - Sundance, WY

58°F

Today's Weather - Castle Rock, CO

54°F

Average Monthly High / Low (°F)

Hot, Freezing, Rainy, Snowy Days: Sundance / Castle Rock

July is the hottest month for Sundance with an average high temperature of 81.2°, which ranks it as cooler than most places in Wyoming. In Sundance, there are 4 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Sundance are August, July and June.

July is the hottest month for Castle Rock with an average high temperature of 85.5°, which ranks it as about average compared to other places in Colorado. In Castle Rock, there are 3 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Castle Rock are June, September and August.

December has the coldest nighttime temperatures for Sundance with an average of 12.0°. This is warmer than most places in Wyoming.

December has the coldest nighttime temperatures for Castle Rock with an average of 18.1°. This is one of the warmest places in Colorado.

In Sundance, there are 11.0 days annually when the high temperature is over 90°, which is cooler than most places in Wyoming.

In Castle Rock, there are 14.9 days annually when the high temperature is over 90°, which is cooler than most places in Colorado.

In Sundance, there are 184.5 days annually when the nighttime low temperature falls below freezing, which is about average compared to other places in Wyoming.

In Castle Rock, there are 156.4 days annually when the nighttime low temperature falls below freezing, which is warmer than most places in Colorado.

In Sundance, there are 16.5 days annually when the nighttime low temperature falls below zero°, which is warmer than most places in Wyoming.

In Castle Rock, there are 5.6 days annually when the nighttime low temperature falls below zero°, which is warmer than most places in Colorado.

May is the wettest month in Sundance with 3.4 inches of rain, and the driest month is January with 0.8 inches. The wettest season is Summer with 33% of yearly precipitation and 12% occurs in Spring, which is the driest season. The annual rainfall of 21.6 inches in Sundance means that it is one of the wettest places in Wyoming.


August is the wettest month in Castle Rock with 2.6 inches of rain, and the driest month is January with 0.6 inches. The wettest season is Autumn with 40% of yearly precipitation and 10% occurs in Spring, which is the driest season. The annual rainfall of 18.6 inches in Castle Rock means that it is wetter than most places in Colorado.

May is the rainiest month in Sundance with 12.0 days of rain, and September is the driest month with only 7.1 rainy days. There are 107.1 rainy days annually in Sundance, which is rainier than most places in Wyoming. The rainiest season is Summer when it rains 30% of the time and the driest is Winter with only a 21% chance of a rainy day.

August is the rainiest month in Castle Rock with 9.9 days of rain, and January is the driest month with only 3.3 rainy days. There are 70.0 rainy days annually in Castle Rock, which is less rainy than most places in Colorado. The rainiest season is Autumn when it rains 37% of the time and the driest is Spring with only a 15% chance of a rainy day.

An annual snowfall of 113.0 inches in Sundance means that it is one of the snowiest places in Wyoming.

An annual snowfall of 78.3 inches in Castle Rock means that it is snowier than most places in Colorado.

April is the snowiest month in Sundance with 19.7 inches of snow, and 9 months of the year have significant snowfall.

March is the snowiest month in Castle Rock with 16.8 inches of snow, and 9 months of the year have significant snowfall.