2025 Compare Climate & Weather:
Richmond, TX vs O'Fallon, IL

Highlights

On average, there are 202 sunny days per year in O'Fallon. Richmond averages 205 sunny days per year. The US average is 205 sunny days.

O'Fallon, Illinois gets 43.1 inches of rain, on average, per year. Richmond, Texas gets 48.9 inches of rain, on average, per year. The US average is 38.1 inches of rain per year.

O'Fallon averages 11.6 inches of snow per year. Richmond averages 0 inches of snow per year. The US average is 27.8 inches of snow per year.

Weather Highlights

O'Fallon, Illinois
Summer High: the July high is around 89.2 degrees
Winter Low: the January low is 22
Rain: averages 43.1 inches of rain a year
Snow: averages 11.6 inches of snow a year

Richmond, Texas
Summer High: the July high is around 93.9 degrees
Winter Low: the January low is 42.6
Rain: averages 48.9 inches of rain a year
Snow: averages 0 inches of snow a year

BestPlaces Comfort Index

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

The annual BestPlaces Comfort Index for Richmond is 6.6 (10=best), which means it is less comfortable than most places in Texas.

Today's Weather - Richmond, TX

88°F

Today's Weather - O'Fallon, IL

80°F

Average Monthly High / Low (°F)

Hot, Freezing, Rainy, Snowy Days: Richmond / O'Fallon

August is the hottest month for Richmond with an average high temperature of 94.7°, which ranks it as about average compared to other places in Texas. In Richmond, there are 4 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Richmond are April, November and March.

July is the hottest month for O'Fallon with an average high temperature of 89.2°, which ranks it as one of the hottest places in Illinois. In O'Fallon, there are 3 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for O'Fallon are May, September and October.

January has the coldest nighttime temperatures for Richmond with an average of 42.6°. This is warmer than most places in Texas.

January has the coldest nighttime temperatures for O'Fallon with an average of 22.0°. This is warmer than most places in Illinois.

In Richmond, there are 105.7 days annually when the high temperature is over 90°, which is hotter than most places in Texas.

In O'Fallon, there are 39.8 days annually when the high temperature is over 90°, which is one of the hottest places in Illinois.

In Richmond, there are 9.5 days annually when the nighttime low temperature falls below freezing, which is warmer than most places in Texas.

In O'Fallon, there are 101.4 days annually when the nighttime low temperature falls below freezing, which is warmer than most places in Illinois.

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

In O'Fallon, there are 1.6 days annually when the nighttime low temperature falls below zero°, which is one of the warmest places in Illinois.

October is the wettest month in Richmond with 5.2 inches of rain, and the driest month is February with 3.0 inches. The wettest season is Winter with 30% of yearly precipitation and 21% occurs in Spring, which is the driest season. The annual rainfall of 48.9 inches in Richmond means that it is wetter than most places in Texas.


May is the wettest month in O'Fallon with 4.9 inches of rain, and the driest month is February with 2.4 inches. The wettest season is Summer with 28% of yearly precipitation and 18% occurs in Spring, which is the driest season. The annual rainfall of 43.1 inches in O'Fallon means that it is wetter than most places in Illinois.

December is the rainiest month in Richmond with 8.7 days of rain, and April is the driest month with only 5.8 rainy days. There are 92.0 rainy days annually in Richmond, which is rainier than most places in Texas. The rainiest season is Spring when it rains 28% of the time and the driest is Summer with only a 21% chance of a rainy day.

May is the rainiest month in O'Fallon with 10.9 days of rain, and February is the driest month with only 6.6 rainy days. There are 96.4 rainy days annually in O'Fallon, which is one of the least rainy places in Illinois. The rainiest season is Summer when it rains 30% of the time and the driest is Spring with only a 22% chance of a rainy day.

There is rarely any recorded snowfall in Richmond, ranking it as one of the least snowy places in Texas.

An annual snowfall of 11.6 inches in O'Fallon means that it is less snowy than most places in Illinois.

Any measurable snowfall is a rare occurance in Richmond.

January is the snowiest month in O'Fallon with 3.8 inches of snow, and 4 months of the year have significant snowfall.