2025 Compare Climate & Weather:
Naperville, IL vs Harrisburg, PA

Highlights

On average, there are 193 sunny days per year in Harrisburg. Naperville averages 189 sunny days per year. The US average is 205 sunny days.

Harrisburg, Pennsylvania gets 41.8 inches of rain, on average, per year. Naperville, Illinois gets 38.6 inches of rain, on average, per year. The US average is 38.1 inches of rain per year.

Harrisburg averages 25.8 inches of snow per year. Naperville averages 28.7 inches of snow per year. The US average is 27.8 inches of snow per year.

Weather Highlights

Harrisburg, Pennsylvania
Summer High: the July high is around 85.1 degrees
Winter Low: the January low is 22.4
Rain: averages 41.8 inches of rain a year
Snow: averages 25.8 inches of snow a year

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

BestPlaces Comfort Index

The annual BestPlaces Comfort Index for Harrisburg is 7.2 (10=best), which means it is one of the most pleasant places in Pennsylvania.

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

Today's Weather - Naperville, IL

55°F

Today's Weather - Harrisburg, PA

50°F

Average Monthly High / Low (°F)

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

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.

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

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

January has the coldest nighttime temperatures for Harrisburg with an average of 22.4°. This is one of the warmest places in Pennsylvania.

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 Harrisburg, there are 13.8 days annually when the high temperature is over 90°, which is hotter than most places in Pennsylvania.

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 Harrisburg, there are 105.1 days annually when the nighttime low temperature falls below freezing, which is one of the warmest places in Pennsylvania.

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.

In Harrisburg, there are 0.5 days annually when the nighttime low temperature falls below zero°, which is one of the warmest places in Pennsylvania.

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.


July is the wettest month in Harrisburg with 4.2 inches of rain, and the driest month is February with 2.7 inches. The wettest season is Autumn with 28% of yearly precipitation and 21% occurs in Spring, which is the driest season. The annual rainfall of 41.8 inches in Harrisburg means that it is drier than most places in Pennsylvania.

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.

May is the rainiest month in Harrisburg with 12.6 days of rain, and September is the driest month with only 8.9 rainy days. There are 122.4 rainy days annually in Harrisburg, which is less rainy than most places in Pennsylvania. The rainiest season is Summer when it rains 28% of the time and the driest is Winter with only a 23% chance of a rainy day.

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

An annual snowfall of 25.8 inches in Harrisburg means that it is less snowy than most places in Pennsylvania.

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

February is the snowiest month in Harrisburg with 8.3 inches of snow, and 6 months of the year have significant snowfall.