2025 Compare Climate & Weather:
Williamsville, NY vs Naperville, IL

Highlights

On average, there are 189 sunny days per year in Naperville. Williamsville averages 157 sunny days per year. The US average is 205 sunny days.

Naperville, Illinois gets 38.6 inches of rain, on average, per year. Williamsville, New York gets 39.4 inches of rain, on average, per year. The US average is 38.1 inches of rain per year.

Naperville averages 28.7 inches of snow per year. Williamsville averages 84.3 inches of snow per year. The US average is 27.8 inches of snow per year.

Weather Highlights

Naperville, Illinois
Summer High: the July high is around 83.8 degrees
Winter Low: the January low is 15.1
Rain: averages 38.6 inches of rain a year
Snow: averages 28.7 inches of snow a year

Williamsville, New York
Summer High: the July high is around 81.3 degrees
Winter Low: the January low is 18
Rain: averages 39.4 inches of rain a year
Snow: averages 84.3 inches of snow a year

BestPlaces Comfort Index

The annual BestPlaces Comfort Index for Naperville is 6.9 (10=best), which means it is less comfortable than most places in Illinois.

The annual BestPlaces Comfort Index for Williamsville is 6.5 (10=best), which means it is less comfortable than most places in New York.

Today's Weather - Williamsville, NY

64°F

Today's Weather - Naperville, IL

62°F

Average Monthly High / Low (°F)

Hot, Freezing, Rainy, Snowy Days: Williamsville / Naperville

July is the hottest month for Williamsville with an average high temperature of 81.3°, which ranks it as about average compared to other places in New York. In Williamsville, there are 4 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Williamsville are June, August and July.

July is the hottest month for Naperville with an average high temperature of 83.8°, which ranks it as cooler than most places in Illinois. In Naperville, there are 5 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Naperville are June, September and August.

January has the coldest nighttime temperatures for Williamsville with an average of 18.0°. This is warmer than most places in New York.

January has the coldest nighttime temperatures for Naperville with an average of 15.1°. This is colder than most places in Illinois.

In Williamsville, there are 4.0 days annually when the high temperature is over 90°, which is cooler than most places in New York.

In Naperville, there are 8.6 days annually when the high temperature is over 90°, which is one of the coolest places in Illinois.

In Williamsville, there are 128.1 days annually when the nighttime low temperature falls below freezing, which is about average compared to other places in New York.

In Naperville, there are 135.4 days annually when the nighttime low temperature falls below freezing, which is colder than most places in Illinois.

In Williamsville, there are 2.8 days annually when the nighttime low temperature falls below zero°, which is warmer than most places in New York.

In Naperville, there are 6.1 days annually when the nighttime low temperature falls below zero°, which is about average compared to other places in Illinois.

November is the wettest month in Williamsville with 3.8 inches of rain, and the driest month is February with 2.4 inches. The wettest season is Winter with 28% of yearly precipitation and 22% occurs in Spring, which is the driest season. The annual rainfall of 39.4 inches in Williamsville means that it is drier than most places in New York.


August is the wettest month in Naperville with 4.2 inches of rain, and the driest month is January with 1.9 inches. The wettest season is Autumn with 32% of yearly precipitation and 16% occurs in Spring, which is the driest season. The annual rainfall of 38.6 inches in Naperville means that it is about average compared to other places in Illinois.

January is the rainiest month in Williamsville with 18.3 days of rain, and August is the driest month with only 10.2 rainy days. There are 161.3 rainy days annually in Williamsville, which is rainier than most places in New York. The rainiest season is Spring when it rains 31% of the time and the driest is Autumn with only a 20% chance of a rainy day.

May is the rainiest month in Naperville with 12.0 days of rain, and September is the driest month with only 7.9 rainy days. There are 120.3 rainy days annually in Naperville, which is rainier than most places in Illinois. The rainiest season is Summer when it rains 28% of the time and the driest is Winter with only a 22% chance of a rainy day.

An annual snowfall of 84.3 inches in Williamsville means that it is snowier than most places in New York.

An annual snowfall of 28.7 inches in Naperville means that it is snowier than most places in Illinois.

January is the snowiest month in Williamsville with 23.1 inches of snow, and 7 months of the year have significant snowfall.

January is the snowiest month in Naperville with 9.1 inches of snow, and 6 months of the year have significant snowfall.