2025 Compare Climate & Weather:
Santa Rosa, CA vs Vacaville, CA

Highlights

On average, there are 260 sunny days per year in Vacaville. Santa Rosa averages 256 sunny days per year. The US average is 205 sunny days.

Vacaville, California gets 25.2 inches of rain, on average, per year. Santa Rosa, California gets 38.2 inches of rain, on average, per year. The US average is 38.1 inches of rain per year.

Vacaville averages 0 inches of snow per year. Santa Rosa averages 0 inches of snow per year. The US average is 27.8 inches of snow per year.

Weather Highlights

Vacaville, California
Summer High: the July high is around 93.4 degrees
Winter Low: the January low is 38.7
Rain: averages 25.2 inches of rain a year
Snow: averages 0 inches of snow a year

Santa Rosa, California
Summer High: the July high is around 83.8 degrees
Winter Low: the January low is 38
Rain: averages 38.2 inches of rain a year
Snow: averages 0 inches of snow a year

BestPlaces Comfort Index

The annual BestPlaces Comfort Index for Vacaville is 8.2 (10=best), which means it is about average compared to other places in California.

The annual BestPlaces Comfort Index for Santa Rosa is 8.3 (10=best), which means it is more comfortable than most places in California.

Today's Weather - Santa Rosa, CA

66°F

Today's Weather - Vacaville, CA

72°F

Average Monthly High / Low (°F)

Hot, Freezing, Rainy, Snowy Days: Santa Rosa / Vacaville

August is the hottest month for Santa Rosa with an average high temperature of 84.1°, which ranks it as cooler than most places in California. In Santa Rosa, there are 7 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Santa Rosa are October, May and June.

July is the hottest month for Vacaville with an average high temperature of 93.4°, which ranks it as warmer than most places in California. In Vacaville, there are 3 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Vacaville are October, May and April.

December has the coldest nighttime temperatures for Santa Rosa with an average of 37.5°. This is about average compared to other places in California.

December has the coldest nighttime temperatures for Vacaville with an average of 38.6°. This is about average compared to other places in California.

In Santa Rosa, there are 31.5 days annually when the high temperature is over 90°, which is cooler than most places in California.

In Vacaville, there are 77.5 days annually when the high temperature is over 90°, which is hotter than most places in California.

In Santa Rosa, there are 22.4 days annually when the nighttime low temperature falls below freezing, which is colder than most places in California.

In Vacaville, there are 11.9 days annually when the nighttime low temperature falls below freezing, which is warmer than most places in California.

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

December is the wettest month in Santa Rosa with 7.4 inches of rain, and the driest month is July with 0.0 inches. The wettest season is Spring with 57% of yearly precipitation and 1% occurs in Autumn, which is the driest season. The annual rainfall of 38.2 inches in Santa Rosa means that it is wetter than most places in California.


January is the wettest month in Vacaville with 5.1 inches of rain, and the driest month is July with 0.0 inches. The wettest season is Spring with 60% of yearly precipitation and 0% occurs in Autumn, which is the driest season. The annual rainfall of 25.2 inches in Vacaville means that it is wetter than most places in California.

January is the rainiest month in Santa Rosa with 12.8 days of rain, and July is the driest month with only 0.2 rainy days. There are 75.7 rainy days annually in Santa Rosa, which is rainier than most places in California. The rainiest season is Spring when it rains 49% of the time and the driest is Autumn with only a 2% chance of a rainy day.

January is the rainiest month in Vacaville with 12.0 days of rain, and July is the driest month with only 0.0 rainy days. There are 64.5 rainy days annually in Vacaville, which is rainier than most places in California. The rainiest season is Spring when it rains 52% of the time and the driest is Autumn with only a 2% chance of a rainy day.

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

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

Any measurable snowfall is a rare occurance in Santa Rosa.

Any measurable snowfall is a rare occurance in Vacaville.