2025 Compare Climate & Weather:
San Diego, CA vs Castle Rock, CO

Highlights

On average, there are 243 sunny days per year in Castle Rock. San Diego averages 266 sunny days per year. The US average is 205 sunny days.

Castle Rock, Colorado gets 18.6 inches of rain, on average, per year. San Diego, California gets 11.7 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. San Diego averages 0 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

San Diego, California
Summer High: the July high is around 78.5 degrees
Winter Low: the January low is 45.6
Rain: averages 11.7 inches of rain a year
Snow: averages 0 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 San Diego is 9.2 (10=best), which means it is one of the most pleasant places in California.

Today's Weather - San Diego, CA

58°F

Today's Weather - Castle Rock, CO

54°F

Average Monthly High / Low (°F)

Hot, Freezing, Rainy, Snowy Days: San Diego / Castle Rock

August is the hottest month for San Diego with an average high temperature of 80.2°, which ranks it as cooler than most places in California. In San Diego, there are 7 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for San Diego are July, September and August.

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 San Diego with an average of 45.3°. This is one of the warmest places in California.

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 San Diego, there are 13.4 days annually when the high temperature is over 90°, which is cooler than most places in California.

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 San Diego, there are 0.7 days annually when the nighttime low temperature falls below freezing, which is one of the warmest places in California.

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 San Diego, there are 0.0 days annually when the nighttime low temperature falls below zero°, which is about average compared to other places in California.

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.

February is the wettest month in San Diego with 2.5 inches of rain, and the driest month is August with 0.0 inches. The wettest season is Spring with 55% of yearly precipitation and 2% occurs in Autumn, which is the driest season. The annual rainfall of 11.7 inches in San Diego means that it is drier than most places in California.


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.

February is the rainiest month in San Diego with 6.8 days of rain, and August is the driest month with only 0.4 rainy days. There are 38.4 rainy days annually in San Diego, which is less rainy than most places in California. The rainiest season is Spring when it rains 48% of the time and the driest is Autumn with only a 4% 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.

There is rarely any recorded snowfall in San Diego, ranking it as one of the least snowy places in California.

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

Any measurable snowfall is a rare occurance in San Diego.

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