2025 Compare Climate & Weather:
San Tan Valley, AZ vs Coralville, IA

Highlights

On average, there are 198 sunny days per year in Coralville. San Tan Valley averages 292 sunny days per year. The US average is 205 sunny days.

Coralville, Iowa gets 36.9 inches of rain, on average, per year. San Tan Valley, Arizona gets 9.9 inches of rain, on average, per year. The US average is 38.1 inches of rain per year.

Coralville averages 26.8 inches of snow per year. San Tan Valley averages 0 inches of snow per year. The US average is 27.8 inches of snow per year.

Weather Highlights

Coralville, Iowa
Summer High: the July high is around 85.1 degrees
Winter Low: the January low is 13.2
Rain: averages 36.9 inches of rain a year
Snow: averages 26.8 inches of snow a year

San Tan Valley, Arizona
Summer High: the July high is around 105 degrees
Winter Low: the January low is 39.4
Rain: averages 9.9 inches of rain a year
Snow: averages 0 inches of snow a year

BestPlaces Comfort Index

The annual BestPlaces Comfort Index for Coralville is 7.0 (10=best), which means it is more comfortable than most places in Iowa.

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

Today's Weather - San Tan Valley, AZ

54°F

Today's Weather - Coralville, IA

45°F

Average Monthly High / Low (°F)

Hot, Freezing, Rainy, Snowy Days: San Tan Valley / Coralville

July is the hottest month for San Tan Valley with an average high temperature of 105.0°, which ranks it as warmer than most places in Arizona. In San Tan Valley, there are 3 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for San Tan Valley are March, November and April.

July is the hottest month for Coralville with an average high temperature of 85.1°, which ranks it as warmer than most places in Iowa. In Coralville, there are 4 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Coralville are September, June and August.

December has the coldest nighttime temperatures for San Tan Valley with an average of 38.3°. This is warmer than most places in Arizona.

January has the coldest nighttime temperatures for Coralville with an average of 13.2°. This is warmer than most places in Iowa.

In San Tan Valley, there are 165.5 days annually when the high temperature is over 90°, which is hotter than most places in Arizona.

In Coralville, there are 16.4 days annually when the high temperature is over 90°, which is hotter than most places in Iowa.

In San Tan Valley, there are 14.2 days annually when the nighttime low temperature falls below freezing, which is warmer than most places in Arizona.

In Coralville, there are 133.8 days annually when the nighttime low temperature falls below freezing, which is warmer than most places in Iowa.

In San Tan Valley, 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 Coralville, there are 12.4 days annually when the nighttime low temperature falls below zero°, which is warmer than most places in Iowa.

August is the wettest month in San Tan Valley with 1.5 inches of rain, and the driest month is June with 0.0 inches. The wettest season is Spring with 35% of yearly precipitation and 18% occurs in Summer, which is the driest season. The annual rainfall of 9.9 inches in San Tan Valley means that it is drier than most places in Arizona.


July is the wettest month in Coralville with 4.8 inches of rain, and the driest month is January with 1.0 inches. The wettest season is Autumn with 39% of yearly precipitation and 10% occurs in Spring, which is the driest season. The annual rainfall of 36.9 inches in Coralville means that it is wetter than most places in Iowa.

August is the rainiest month in San Tan Valley with 4.6 days of rain, and June is the driest month with only 0.3 rainy days. There are 32.2 rainy days annually in San Tan Valley, 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 18% chance of a rainy day.

May is the rainiest month in Coralville with 11.2 days of rain, and February is the driest month with only 5.4 rainy days. There are 97.4 rainy days annually in Coralville, which is about average compared to other places in Iowa. The rainiest season is Summer when it rains 29% of the time and the driest is Spring with only a 19% chance of a rainy day.

There is rarely any recorded snowfall in San Tan Valley, ranking it as one of the least snowy places in Arizona.

An annual snowfall of 26.8 inches in Coralville means that it is less snowy than most places in Iowa.

Any measurable snowfall is a rare occurance in San Tan Valley.

December is the snowiest month in Coralville with 8.1 inches of snow, and 6 months of the year have significant snowfall.