2025 Compare Climate & Weather:
St. Simons, GA vs Charleston, SC

Highlights

On average, there are 209 sunny days per year in Charleston. St. Simons averages 221 sunny days per year. The US average is 205 sunny days.

Charleston, South Carolina gets 48.3 inches of rain, on average, per year. St. Simons, Georgia gets 48.2 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. St. Simons averages 0.1 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

St. Simons, Georgia
Summer High: the July high is around 91 degrees
Winter Low: the January low is 42.1
Rain: averages 48.2 inches of rain a year
Snow: averages 0.1 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 St. Simons is 7.1 (10=best), which means it is one of the least comfortable places in Georgia.

Today's Weather - St. Simons, GA

73°F

Today's Weather - Charleston, SC

71°F

Average Monthly High / Low (°F)

Hot, Freezing, Rainy, Snowy Days: St. Simons / Charleston

July is the hottest month for St. Simons with an average high temperature of 91.0°, which ranks it as about average compared to other places in Georgia. In St. Simons, there are 4 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for St. Simons are October, April and May.

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 St. Simons with an average of 42.1°. This is one of the warmest places in Georgia.

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 St. Simons, there are 51.3 days annually when the high temperature is over 90°, which is about average compared to other places in Georgia.

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 St. Simons, there are 10.4 days annually when the nighttime low temperature falls below freezing, which is one of the warmest places in Georgia.

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

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.

August is the wettest month in St. Simons with 6.8 inches of rain, and the driest month is November with 2.2 inches. The wettest season is Autumn with 35% of yearly precipitation and 19% occurs in Summer, which is the driest season. The annual rainfall of 48.2 inches in St. Simons means that it is drier than most places in Georgia.


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.

August is the rainiest month in St. Simons with 12.2 days of rain, and April is the driest month with only 5.8 rainy days. There are 101.7 rainy days annually in St. Simons, which is about average compared to other places in Georgia. The rainiest season is Autumn when it rains 33% of the time and the driest is Summer with only a 19% 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.

An annual snowfall of 0.1 inches in St. Simons means that it is less snowy than most places in Georgia.

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

December is the snowiest month in St. Simons with 0.1 inches of snow, and no months of the year have significant snowfall.

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