2025 Compare Climate & Weather:
Phoenix, AZ vs San Diego, CA

Highlights

On average, there are 266 sunny days per year in San Diego. Phoenix averages 299 sunny days per year. The US average is 205 sunny days.

San Diego, California gets 11.7 inches of rain, on average, per year. Phoenix, Arizona gets 9.2 inches of rain, on average, per year. The US average is 38.1 inches of rain per year.

San Diego averages 0 inches of snow per year. Phoenix averages 0 inches of snow per year. The US average is 27.8 inches of snow per year.

Weather Highlights

San Diego, California
Summer High: the July high is around 78.5 degrees
Winter Low: the January low is 45.6
Rain: averages 11.7 inches of rain a year
Snow: averages 0 inches of snow a year

Phoenix, Arizona
Summer High: the July high is around 104.5 degrees
Winter Low: the January low is 43.2
Rain: averages 9.2 inches of rain a year
Snow: averages 0 inches of snow a year

BestPlaces Comfort Index

The annual BestPlaces Comfort Index for San Diego is 9.2 (10=best), which means it is one of the most pleasant places in California.

The annual BestPlaces Comfort Index for Phoenix is 7.3 (10=best), which means it is less comfortable than most places in Arizona.

Today's Weather - Phoenix, AZ

78°F

Today's Weather - San Diego, CA

61°F

Average Monthly High / Low (°F)

Hot, Freezing, Rainy, Snowy Days: Phoenix / San Diego

July is the hottest month for Phoenix with an average high temperature of 104.5°, which ranks it as warmer than most places in Arizona. In Phoenix, there are 4 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Phoenix are March, November and April.

August is the hottest month for San Diego with an average high temperature of 80.2°, which ranks it as cooler than most places in California. In San Diego, there are 7 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for San Diego are July, September and August.

December has the coldest nighttime temperatures for Phoenix with an average of 42.2°. This is one of the warmest places in Arizona.

December has the coldest nighttime temperatures for San Diego with an average of 45.3°. This is one of the warmest places in California.

In Phoenix, there are 163.2 days annually when the high temperature is over 90°, which is hotter than most places in Arizona.

In San Diego, there are 13.4 days annually when the high temperature is over 90°, which is cooler than most places in California.

In Phoenix, there are 3.2 days annually when the nighttime low temperature falls below freezing, which is warmer than most places in Arizona.

In San Diego, there are 0.7 days annually when the nighttime low temperature falls below freezing, which is one of the warmest places in California.

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

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

August is the wettest month in Phoenix with 1.1 inches of rain, and the driest month is June with 0.0 inches. The wettest season is Spring with 35% of yearly precipitation and 16% occurs in Summer, which is the driest season. The annual rainfall of 9.2 inches in Phoenix means that it is drier than most places in Arizona.


February is the wettest month in San Diego with 2.5 inches of rain, and the driest month is August with 0.0 inches. The wettest season is Spring with 55% of yearly precipitation and 2% occurs in Autumn, which is the driest season. The annual rainfall of 11.7 inches in San Diego means that it is drier than most places in California.

August is the rainiest month in Phoenix with 4.0 days of rain, and June is the driest month with only 0.4 rainy days. There are 33.1 rainy days annually in Phoenix, which is less rainy than most places in Arizona. The rainiest season is Spring when it rains 34% of the time and the driest is Summer with only a 20% chance of a rainy day.

February is the rainiest month in San Diego with 6.8 days of rain, and August is the driest month with only 0.4 rainy days. There are 38.4 rainy days annually in San Diego, which is less rainy 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 Phoenix, ranking it as one of the least snowy places in Arizona.

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

Any measurable snowfall is a rare occurance in Phoenix.

Any measurable snowfall is a rare occurance in San Diego.