2025 Compare Climate & Weather:
Diamond Bar, CA vs San Luis Obispo, CA

Highlights

On average, there are 287 sunny days per year in San Luis Obispo. Diamond Bar averages 286 sunny days per year. The US average is 205 sunny days.

San Luis Obispo, California gets 20 inches of rain, on average, per year. Diamond Bar, California gets 18.8 inches of rain, on average, per year. The US average is 38.1 inches of rain per year.

San Luis Obispo averages 0 inches of snow per year. Diamond Bar averages 0 inches of snow per year. The US average is 27.8 inches of snow per year.

Weather Highlights

San Luis Obispo, California
Summer High: the July high is around 73.7 degrees
Winter Low: the January low is 42.8
Rain: averages 20 inches of rain a year
Snow: averages 0 inches of snow a year

Diamond Bar, California
Summer High: the July high is around 90.9 degrees
Winter Low: the January low is 42.5
Rain: averages 18.8 inches of rain a year
Snow: averages 0 inches of snow a year

BestPlaces Comfort Index

The annual BestPlaces Comfort Index for San Luis Obispo is 8.8 (10=best), which means it is more comfortable than most places in California.

The annual BestPlaces Comfort Index for Diamond Bar is 8.8 (10=best), which means it is more comfortable than most places in California.

Today's Weather - Diamond Bar, CA

66°F

Today's Weather - San Luis Obispo, CA

67°F

Average Monthly High / Low (°F)

Hot, Freezing, Rainy, Snowy Days: Diamond Bar / San Luis Obispo

August is the hottest month for Diamond Bar with an average high temperature of 92.6°, which ranks it as about average compared to other places in California. In Diamond Bar, there are 6 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Diamond Bar are May, October and April.

September is the hottest month for San Luis Obispo with an average high temperature of 75.3°, which ranks it as one of the coolest places in California. In San Luis Obispo, there are 5 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for San Luis Obispo are September, August and July.

December has the coldest nighttime temperatures for Diamond Bar with an average of 41.3°. This is warmer than most places in California.

December has the coldest nighttime temperatures for San Luis Obispo with an average of 42.2°. This is warmer than most places in California.

In Diamond Bar, there are 72.5 days annually when the high temperature is over 90°, which is hotter than most places in California.

In San Luis Obispo, there are 6.3 days annually when the high temperature is over 90°, which is cooler than most places in California.

In Diamond Bar, there are 4.3 days annually when the nighttime low temperature falls below freezing, which is warmer than most places in California.

In San Luis Obispo, there are 3.5 days annually when the nighttime low temperature falls below freezing, which is warmer than most places in California.

In Diamond Bar, 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 San Luis Obispo, 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 Diamond Bar with 4.7 inches of rain, and the driest month is July with 0.0 inches. The wettest season is Spring with 60% of yearly precipitation and 1% occurs in Autumn, which is the driest season. The annual rainfall of 18.8 inches in Diamond Bar means that it is about average compared to other places in California.


February is the wettest month in San Luis Obispo with 4.2 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 20.0 inches in San Luis Obispo means that it is about average compared to other places in California.

February is the rainiest month in Diamond Bar with 5.9 days of rain, and July is the driest month with only 0.2 rainy days. There are 32.3 rainy days annually in Diamond Bar, which is less rainy 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 4% chance of a rainy day.

February is the rainiest month in San Luis Obispo with 9.2 days of rain, and July is the driest month with only 0.4 rainy days. There are 50.5 rainy days annually in San Luis Obispo, 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 Diamond Bar, ranking it as one of the least snowy places in California.

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

Any measurable snowfall is a rare occurance in Diamond Bar.

Any measurable snowfall is a rare occurance in San Luis Obispo.