San Bruno, CA Climate

The climate in San Bruno, CA is generally mild and pleasant year-round. During the summer months, daytime temperatures typically reach the high 70s to mid 80s with nighttime temperatures in the lower 50s. In the winter months, daytime highs are usually around 60 degrees and nighttime lows hover around 40 degrees. Precipitation is moderate throughout the year, with the most rain occurring from November through April. The area also has an average of almost 280 sunny days per year.

San Bruno, California gets 26 inches of rain, on average, per year. The US average is 38 inches of rain per year.

San Bruno averages 0 inches of snow per year. The US average is 28 inches of snow per year.

On average, there are 262 sunny days per year in San Bruno. The US average is 205 sunny days.

San Bruno gets some kind of precipitation, on average, 69 days per year. Precipitation is rain, snow, sleet, or hail that falls to the ground. In order for precipitation to be counted you have to get at least .01 inches on the ground to measure.

Weather Highlights

Summer High: the July high is around 70 degrees
Winter Low: the January low is 46
Rain: averages 26 inches of rain a year
Snow: averages 0 inches of snow a year

Bestplaces Comfort Index

The annual BestPlaces Comfort Index for San Bruno is 8.5 (10=best), which means it is more comfortable than most places in California.

9.4 Summer - 7.6 Winter

September, August and July are the most pleasant months in San Bruno, while January and December are the least comfortable months.

Climate	San Bruno, California	United States
	25.5 in.	38.1 in.
	0.0 in.	27.8 in.
	69.1 days	106.2 days
	262 days	205 days
	69.8°	85.8°
	45.9°	21.7°
	8.5	7
	4.9	4.3
	20 ft.	2443 ft.

Climate

YOU SHOULD KNOW

Many people confuse weather and climate but they are different. Weather is the conditions of the atmosphere over a short period of time, and climate is how the atmosphere is over long periods of time.

Weather is how the atmosphere is behaving and its effects upon life and human activities. Weather can change from minute-to-minute. Most people think of weather in terms of temperature, humidity, precipitation, cloudiness, brightness, visibility, wind, and atmospheric pressure.

Climate is the description of the long-term pattern of weather in a place. Climate can mean the average weather for a particular region and time period taken over 30 years. Climate is the average of weather over time.

September is the hottest month for San Bruno with an average high temperature of 72.1°, which ranks it as one of the coolest places in California. In San Bruno, there are 2 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for San Bruno are September, August and July.

In San Bruno, there are 2.6 days annually when the high temperature is over 90°, which is one of the coolest places in California.

January has the coldest nighttime temperatures for San Bruno with an average of 45.9°. This is one of the warmest places in California.

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

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

Humidity in San Bruno is generally quite low and comfortable. There are few days during the summer when the humidity becomes unpleasant. The most humid months (but still comfortable) are August, July and September.

January is the wettest month in San Bruno with 5.0 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 25.5 inches in San Bruno means that it is wetter than most places in California.

January is the rainiest month in San Bruno with 11.2 days of rain, and July is the driest month with only 0.3 rainy days. There are 69.1 rainy days annually in San Bruno, which is rainier than most places in California. The rainiest season is Spring when it rains 48% of the time and the driest is Autumn with only a 4% chance of a rainy day.

There is rarely any recorded snowfall in San Bruno, ranking it as one of the least snowy places in California. Any measurable snowfall is a rare occurance in San Bruno.