2025 Compare Climate & Weather:
Chicago, IL vs Portland, ME

Highlights

On average, there are 203 sunny days per year in Portland. Chicago averages 189 sunny days per year. The US average is 205 sunny days.

Portland, Maine gets 48.9 inches of rain, on average, per year. Chicago, Illinois gets 38.2 inches of rain, on average, per year. The US average is 38.1 inches of rain per year.

Portland averages 61 inches of snow per year. Chicago averages 35.1 inches of snow per year. The US average is 27.8 inches of snow per year.

Weather Highlights

Portland, Maine
Summer High: the July high is around 78.8 degrees
Winter Low: the January low is 10.8
Rain: averages 48.9 inches of rain a year
Snow: averages 61 inches of snow a year

Chicago, Illinois
Summer High: the July high is around 83.9 degrees
Winter Low: the January low is 19.2
Rain: averages 38.2 inches of rain a year
Snow: averages 35.1 inches of snow a year

BestPlaces Comfort Index

The annual BestPlaces Comfort Index for Portland is 6.5 (10=best), which means it is more comfortable than most places in Maine.

The annual BestPlaces Comfort Index for Chicago is 7.0 (10=best), which means it is about average compared to other places in Illinois.

Today's Weather - Chicago, IL

57°F

Today's Weather - Portland, ME

62°F

Average Monthly High / Low (°F)

Hot, Freezing, Rainy, Snowy Days: Chicago / Portland

July is the hottest month for Chicago with an average high temperature of 83.9°, which ranks it as cooler than most places in Illinois. In Chicago, there are 4 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Chicago are June, September and August.

July is the hottest month for Portland with an average high temperature of 78.8°, which ranks it as about average compared to other places in Maine. In Portland, there are 4 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Portland are August, July and June.

January has the coldest nighttime temperatures for Chicago with an average of 19.2°. This is warmer than most places in Illinois.

January has the coldest nighttime temperatures for Portland with an average of 10.8°. This is warmer than most places in Maine.

In Chicago, there are 13.6 days annually when the high temperature is over 90°, which is cooler than most places in Illinois.

In Portland, there are 3.8 days annually when the high temperature is over 90°, which is hotter than most places in Maine.

In Chicago, there are 103.9 days annually when the nighttime low temperature falls below freezing, which is warmer than most places in Illinois.

In Portland, there are 154.5 days annually when the nighttime low temperature falls below freezing, which is warmer than most places in Maine.

In Chicago, there are 4.0 days annually when the nighttime low temperature falls below zero°, which is warmer than most places in Illinois.

In Portland, there are 12.2 days annually when the nighttime low temperature falls below zero°, which is warmer than most places in Maine.

August is the wettest month in Chicago with 4.2 inches of rain, and the driest month is January with 2.0 inches. The wettest season is Autumn with 31% of yearly precipitation and 17% occurs in Spring, which is the driest season. The annual rainfall of 38.2 inches in Chicago means that it is drier than most places in Illinois.


November is the wettest month in Portland with 5.0 inches of rain, and the driest month is August with 3.3 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 48.9 inches in Portland means that it is about average compared to other places in Maine.

May is the rainiest month in Chicago with 11.5 days of rain, and February is the driest month with only 8.4 rainy days. There are 124.8 rainy days annually in Chicago, which is one of the rainiest places in Illinois. The rainiest season is Summer when it rains 27% of the time and the driest is Spring with only a 24% chance of a rainy day.

May is the rainiest month in Portland with 12.4 days of rain, and February is the driest month with only 9.2 rainy days. There are 128.3 rainy days annually in Portland, which is about average compared to other places in Maine. The rainiest season is Summer when it rains 27% of the time and the driest is Spring with only a 24% chance of a rainy day.

An annual snowfall of 35.1 inches in Chicago means that it is one of the snowiest places in Illinois.

An annual snowfall of 61.0 inches in Portland means that it is less snowy than most places in Maine.

January is the snowiest month in Chicago with 11.0 inches of snow, and 6 months of the year have significant snowfall.

January is the snowiest month in Portland with 18.1 inches of snow, and 6 months of the year have significant snowfall.