2025 Compare Climate & Weather:
Foster City, CA vs Granite Bay, CA

Highlights

On average, there are 265 sunny days per year in Granite Bay. Foster City averages 262 sunny days per year. The US average is 205 sunny days.

Granite Bay, California gets 21.4 inches of rain, on average, per year. Foster City, California gets 19.1 inches of rain, on average, per year. The US average is 38.1 inches of rain per year.

Granite Bay averages 0 inches of snow per year. Foster City averages 0 inches of snow per year. The US average is 27.8 inches of snow per year.

Weather Highlights

Granite Bay, California
Summer High: the July high is around 94.2 degrees
Winter Low: the January low is 39
Rain: averages 21.4 inches of rain a year
Snow: averages 0 inches of snow a year

Foster City, California
Summer High: the July high is around 77.9 degrees
Winter Low: the January low is 41.1
Rain: averages 19.1 inches of rain a year
Snow: averages 0 inches of snow a year

BestPlaces Comfort Index

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

The annual BestPlaces Comfort Index for Foster City is 8.7 (10=best), which means it is more comfortable than most places in California.

Today's Weather - Foster City, CA

52°F

Today's Weather - Granite Bay, CA

54°F

Average Monthly High / Low (°F)

Hot, Freezing, Rainy, Snowy Days: Foster City / Granite Bay

August is the hottest month for Foster City with an average high temperature of 77.9°, which ranks it as cooler than most places in California. In Foster City, there are 6 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Foster City are August, July and September.

July is the hottest month for Granite Bay with an average high temperature of 94.2°, which ranks it as warmer than most places in California. In Granite Bay, there are 3 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Granite Bay are October, May and April.

December has the coldest nighttime temperatures for Foster City with an average of 41.0°. This is warmer than most places in California.

December has the coldest nighttime temperatures for Granite Bay with an average of 38.9°. This is warmer than most places in California.

In Foster City, there are 10.7 days annually when the high temperature is over 90°, which is cooler than most places in California.

In Granite Bay, there are 78.6 days annually when the high temperature is over 90°, which is hotter than most places in California.

In Foster City, there are 6.1 days annually when the nighttime low temperature falls below freezing, which is warmer than most places in California.

In Granite Bay, there are 9.8 days annually when the nighttime low temperature falls below freezing, which is warmer than most places in California.

In Foster City, 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 Granite Bay, there are 0.0 days annually when the nighttime low temperature falls below zero°, which is about average compared to other places in California.

February is the wettest month in Foster City with 3.8 inches of rain, and the driest month is July with 0.0 inches. The wettest season is Spring with 59% of yearly precipitation and 1% occurs in Autumn, which is the driest season. The annual rainfall of 19.1 inches in Foster City means that it is about average compared to other places in California.


February is the wettest month in Granite Bay with 4.0 inches of rain, and the driest month is July with 0.0 inches. The wettest season is Spring with 54% of yearly precipitation and 1% occurs in Autumn, which is the driest season. The annual rainfall of 21.4 inches in Granite Bay means that it is wetter than most places in California.

January is the rainiest month in Foster City with 10.7 days of rain, and July is the driest month with only 0.1 rainy days. There are 62.0 rainy days annually in Foster City, 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.

January is the rainiest month in Granite Bay with 10.4 days of rain, and July is the driest month with only 0.1 rainy days. There are 59.4 rainy days annually in Granite Bay, 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 3% chance of a rainy day.

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

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

Any measurable snowfall is a rare occurance in Foster City.

Any measurable snowfall is a rare occurance in Granite Bay.