2025 Compare Climate & Weather:
Foster City, CA vs Hayward, CA

Highlights

On average, there are 257 sunny days per year in Hayward. Foster City averages 262 sunny days per year. The US average is 205 sunny days.

Hayward, California gets 18 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.

Hayward 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

Hayward, California
Summer High: the July high is around 76.2 degrees
Winter Low: the January low is 42.1
Rain: averages 18 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 Hayward is 8.7 (10=best), which means it is more comfortable than most 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

55°F

Today's Weather - Hayward, CA

56°F

Average Monthly High / Low (°F)

Hot, Freezing, Rainy, Snowy Days: Foster City / Hayward

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.

August is the hottest month for Hayward with an average high temperature of 77.5°, which ranks it as cooler than most places in California. In Hayward, there are 6 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Hayward are August, September and July.

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

January has the coldest nighttime temperatures for Hayward with an average of 42.1°. 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 Hayward, there are 9.6 days annually when the high temperature is over 90°, which is cooler 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 Hayward, there are 2.4 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 Hayward, 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 Hayward with 3.4 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 18.0 inches in Hayward means that it is about average compared to other 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.

December is the rainiest month in Hayward with 11.5 days of rain, and July is the driest month with only 0.1 rainy days. There are 64.7 rainy days annually in Hayward, which is rainier than most places in California. The rainiest season is Spring when it rains 51% of the time and the driest is Autumn with only a 2% 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 Hayward, 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 Hayward.