2025 Compare Climate & Weather:
Petaluma, CA vs Gilroy, CA

Highlights

On average, there are 261 sunny days per year in Gilroy. Petaluma averages 260 sunny days per year. The US average is 205 sunny days.

Gilroy, California gets 21.4 inches of rain, on average, per year. Petaluma, California gets 29.8 inches of rain, on average, per year. The US average is 38.1 inches of rain per year.

Gilroy averages 0 inches of snow per year. Petaluma averages 0 inches of snow per year. The US average is 27.8 inches of snow per year.

Weather Highlights

Gilroy, California
Summer High: the July high is around 83.4 degrees
Winter Low: the January low is 39.6
Rain: averages 21.4 inches of rain a year
Snow: averages 0 inches of snow a year

Petaluma, California
Summer High: the July high is around 83.7 degrees
Winter Low: the January low is 38.7
Rain: averages 29.8 inches of rain a year
Snow: averages 0 inches of snow a year

BestPlaces Comfort Index

The annual BestPlaces Comfort Index for Gilroy is 8.6 (10=best), which means it is more comfortable than most places in California.

The annual BestPlaces Comfort Index for Petaluma is 8.4 (10=best), which means it is more comfortable than most places in California.

Today's Weather - Petaluma, CA

48°F

Today's Weather - Gilroy, CA

51°F

Average Monthly High / Low (°F)

Hot, Freezing, Rainy, Snowy Days: Petaluma / Gilroy

August is the hottest month for Petaluma with an average high temperature of 83.7°, which ranks it as cooler than most places in California. In Petaluma, there are 6 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Petaluma are October, June and May.

July is the hottest month for Gilroy with an average high temperature of 83.4°, which ranks it as cooler than most places in California. In Gilroy, there are 7 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Gilroy are October, June and May.

December has the coldest nighttime temperatures for Petaluma with an average of 38.3°. This is about average compared to other places in California.

January has the coldest nighttime temperatures for Gilroy with an average of 39.6°. This is warmer than most places in California.

In Petaluma, there are 28.1 days annually when the high temperature is over 90°, which is cooler than most places in California.

In Gilroy, there are 29.3 days annually when the high temperature is over 90°, which is cooler than most places in California.

In Petaluma, there are 16.7 days annually when the nighttime low temperature falls below freezing, which is about average compared to other places in California.

In Gilroy, there are 10.3 days annually when the nighttime low temperature falls below freezing, which is warmer than most places in California.

In Petaluma, 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 Gilroy, 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 Petaluma with 5.7 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 29.8 inches in Petaluma means that it is wetter than most places in California.


February is the wettest month in Gilroy with 4.3 inches of rain, and the driest month is July with 0.0 inches. The wettest season is Spring with 59% of yearly precipitation and 0% occurs in Autumn, which is the driest season. The annual rainfall of 21.4 inches in Gilroy means that it is wetter than most places in California.

January is the rainiest month in Petaluma with 12.5 days of rain, and July is the driest month with only 0.2 rainy days. There are 74.8 rainy days annually in Petaluma, 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 Gilroy with 10.1 days of rain, and July is the driest month with only 0.2 rainy days. There are 58.6 rainy days annually in Gilroy, which is about average compared to other 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.

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

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

Any measurable snowfall is a rare occurance in Petaluma.

Any measurable snowfall is a rare occurance in Gilroy.