2025 Compare Climate & Weather:
Santa Rosa, CA vs Hillsboro, OR

Highlights

On average, there are 142 sunny days per year in Hillsboro. Santa Rosa averages 256 sunny days per year. The US average is 205 sunny days.

Hillsboro, Oregon gets 39.2 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.

Hillsboro averages 3.2 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

Hillsboro, Oregon
Summer High: the July high is around 80.8 degrees
Winter Low: the January low is 36.7
Rain: averages 39.2 inches of rain a year
Snow: averages 3.2 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 Hillsboro is 7.5 (10=best), which means it is more comfortable than most places in Oregon.

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

49°F

Today's Weather - Hillsboro, OR

40°F

Average Monthly High / Low (°F)

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

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.

August is the hottest month for Hillsboro with an average high temperature of 81.8°, which ranks it as cooler than most places in Oregon. In Hillsboro, there are 4 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Hillsboro are September, July and August.

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 Hillsboro with an average of 35.7°. This is warmer than most places in Oregon.

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 Hillsboro, there are 13.1 days annually when the high temperature is over 90°, which is cooler than most places in Oregon.

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 Hillsboro, there are 31.8 days annually when the nighttime low temperature falls below freezing, which is warmer than most places in Oregon.

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

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.


December is the wettest month in Hillsboro with 6.3 inches of rain, and the driest month is July with 0.7 inches. The wettest season is Spring with 42% of yearly precipitation and 7% occurs in Autumn, which is the driest season. The annual rainfall of 39.2 inches in Hillsboro means that it is about average compared to other places in Oregon.

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.

November is the rainiest month in Hillsboro with 20.2 days of rain, and August is the driest month with only 3.4 rainy days. There are 156.2 rainy days annually in Hillsboro, which is rainier than most places in Oregon. The rainiest season is Spring when it rains 35% of the time and the driest is Autumn with only a 10% 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.

An annual snowfall of 3.2 inches in Hillsboro means that it is about average compared to other places in Oregon.

Any measurable snowfall is a rare occurance in Santa Rosa.

December is the snowiest month in Hillsboro with 1.4 inches of snow, and 3 months of the year have significant snowfall.