2025 Compare Climate & Weather:
Key West, FL vs Charleston, SC

Highlights

On average, there are 209 sunny days per year in Charleston. Key West averages 260 sunny days per year. The US average is 205 sunny days.

Charleston, South Carolina gets 48.3 inches of rain, on average, per year. Key West, Florida gets 43.8 inches of rain, on average, per year. The US average is 38.1 inches of rain per year.

Charleston averages 0.4 inches of snow per year. Key West averages 0 inches of snow per year. The US average is 27.8 inches of snow per year.

Weather Highlights

Charleston, South Carolina
Summer High: the July high is around 89.9 degrees
Winter Low: the January low is 39.3
Rain: averages 48.3 inches of rain a year
Snow: averages 0.4 inches of snow a year

Key West, Florida
Summer High: the July high is around 89.4 degrees
Winter Low: the January low is 63.6
Rain: averages 43.8 inches of rain a year
Snow: averages 0 inches of snow a year

BestPlaces Comfort Index

The annual BestPlaces Comfort Index for Charleston is 7.2 (10=best), which means it is less comfortable than most places in South Carolina.

The annual BestPlaces Comfort Index for Key West is 6.1 (10=best), which means it is one of the least comfortable places in Florida.

Today's Weather - Key West, FL

85°F

Today's Weather - Charleston, SC

72°F

Average Monthly High / Low (°F)

Hot, Freezing, Rainy, Snowy Days: Key West / Charleston

August is the hottest month for Key West with an average high temperature of 89.6°, which ranks it as one of the coolest places in Florida. In Key West, there are 7 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Key West are March, February and December.

July is the hottest month for Charleston with an average high temperature of 89.9°, which ranks it as cooler than most places in South Carolina. In Charleston, there are 4 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Charleston are October, May and April.

January has the coldest nighttime temperatures for Key West with an average of 63.6°. This is one of the warmest places in Florida.

January has the coldest nighttime temperatures for Charleston with an average of 39.3°. This is one of the warmest places in South Carolina.

In Key West, there are 37.7 days annually when the high temperature is over 90°, which is one of the coolest places in Florida.

In Charleston, there are 41.1 days annually when the high temperature is over 90°, which is cooler than most places in South Carolina.

In Key West, there are 0.0 days annually when the nighttime low temperature falls below freezing, which is one of the warmest places in Florida.

In Charleston, there are 17.5 days annually when the nighttime low temperature falls below freezing, which is one of the warmest places in South Carolina.

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

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

September is the wettest month in Key West with 7.5 inches of rain, and the driest month is February with 1.8 inches. The wettest season is Autumn with 35% of yearly precipitation and 14% occurs in Spring, which is the driest season. The annual rainfall of 43.8 inches in Key West means that it is one of the driest places in Florida.


August is the wettest month in Charleston with 6.7 inches of rain, and the driest month is May with 2.5 inches. The wettest season is Autumn with 36% of yearly precipitation and 19% occurs in Summer, which is the driest season. The annual rainfall of 48.3 inches in Charleston means that it is wetter than most places in South Carolina.

September is the rainiest month in Key West with 15.3 days of rain, and April is the driest month with only 4.4 rainy days. There are 102.0 rainy days annually in Key West, which is one of the least rainy places in Florida. The rainiest season is Autumn when it rains 35% of the time and the driest is Summer with only a 16% chance of a rainy day.

August is the rainiest month in Charleston with 11.7 days of rain, and May is the driest month with only 6.8 rainy days. There are 105.9 rainy days annually in Charleston, which is rainier than most places in South Carolina. The rainiest season is Autumn when it rains 32% of the time and the driest is Summer with only a 21% chance of a rainy day.

There is rarely any recorded snowfall in Key West, ranking it as one of the least snowy places in Florida.

An annual snowfall of 0.4 inches in Charleston means that it is less snowy than most places in South Carolina.

Any measurable snowfall is a rare occurance in Key West.

December is the snowiest month in Charleston with 0.2 inches of snow, and no months of the year have significant snowfall.