2025 Compare Climate & Weather:
South San Francisco, CA vs Pleasanton, CA

Highlights

On average, there are 264 sunny days per year in Pleasanton. South San Francisco averages 259 sunny days per year. The US average is 205 sunny days.

Pleasanton, California gets 18.7 inches of rain, on average, per year. South San Francisco, California gets 21.7 inches of rain, on average, per year. The US average is 38.1 inches of rain per year.

Pleasanton averages 0 inches of snow per year. South San Francisco averages 0 inches of snow per year. The US average is 27.8 inches of snow per year.

Weather Highlights

Pleasanton, California
Summer High: the July high is around 85.4 degrees
Winter Low: the January low is 39.3
Rain: averages 18.7 inches of rain a year
Snow: averages 0 inches of snow a year

South San Francisco, California
Summer High: the July high is around 66.7 degrees
Winter Low: the January low is 45
Rain: averages 21.7 inches of rain a year
Snow: averages 0 inches of snow a year

BestPlaces Comfort Index

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

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

Today's Weather - South San Francisco, CA

60°F

Today's Weather - Pleasanton, CA

62°F

Average Monthly High / Low (°F)

Hot, Freezing, Rainy, Snowy Days: South San Francisco / Pleasanton

September is the hottest month for South San Francisco with an average high temperature of 69.3°, which ranks it as one of the coolest places in California. In South San Francisco, there are 0 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for South San Francisco are September, October and August.

August is the hottest month for Pleasanton with an average high temperature of 85.4°, which ranks it as cooler than most places in California. In Pleasanton, there are 4 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Pleasanton are June, October and May.

January has the coldest nighttime temperatures for South San Francisco with an average of 45.0°. This is one of the warmest places in California.

January has the coldest nighttime temperatures for Pleasanton with an average of 39.3°. This is warmer than most places in California.

In South San Francisco, there are 1.8 days annually when the high temperature is over 90°, which is one of the coolest places in California.

In Pleasanton, there are 36.0 days annually when the high temperature is over 90°, which is cooler than most places in California.

In South San Francisco, there are 0.3 days annually when the nighttime low temperature falls below freezing, which is one of the warmest places in California.

In Pleasanton, there are 11.3 days annually when the nighttime low temperature falls below freezing, which is warmer than most places in California.

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

January is the wettest month in South San Francisco with 4.3 inches of rain, and the driest month is July with 0.0 inches. The wettest season is Spring with 58% of yearly precipitation and 1% occurs in Autumn, which is the driest season. The annual rainfall of 21.7 inches in South San Francisco means that it is wetter than most places in California.


February is the wettest month in Pleasanton with 3.5 inches of rain, and the driest month is July with 0.0 inches. The wettest season is Spring with 55% of yearly precipitation and 1% occurs in Autumn, which is the driest season. The annual rainfall of 18.7 inches in Pleasanton means that it is about average compared to other places in California.

December is the rainiest month in South San Francisco with 11.4 days of rain, and July is the driest month with only 0.2 rainy days. There are 68.4 rainy days annually in South San Francisco, which is rainier than most places in California. The rainiest season is Spring when it rains 50% of the time and the driest is Autumn with only a 3% chance of a rainy day.

December is the rainiest month in Pleasanton with 11.0 days of rain, and July is the driest month with only 0.2 rainy days. There are 64.0 rainy days annually in Pleasanton, which is rainier than most places in California. The rainiest season is Spring when it rains 50% of the time and the driest is Autumn with only a 2% chance of a rainy day.

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

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

Any measurable snowfall is a rare occurance in South San Francisco.

Any measurable snowfall is a rare occurance in Pleasanton.