2025 Compare Climate & Weather:
Gaithersburg, MD vs Hilton Head Island, SC

Highlights

On average, there are 215 sunny days per year in Hilton Head Island. Gaithersburg averages 202 sunny days per year. The US average is 205 sunny days.

Hilton Head Island, South Carolina gets 48.1 inches of rain, on average, per year. Gaithersburg, Maryland gets 42.2 inches of rain, on average, per year. The US average is 38.1 inches of rain per year.

Hilton Head Island averages 0.1 inches of snow per year. Gaithersburg averages 21.4 inches of snow per year. The US average is 27.8 inches of snow per year.

Weather Highlights

Hilton Head Island, South Carolina
Summer High: the July high is around 90.8 degrees
Winter Low: the January low is 39.2
Rain: averages 48.1 inches of rain a year
Snow: averages 0.1 inches of snow a year

Gaithersburg, Maryland
Summer High: the July high is around 85.1 degrees
Winter Low: the January low is 25
Rain: averages 42.2 inches of rain a year
Snow: averages 21.4 inches of snow a year

BestPlaces Comfort Index

The annual BestPlaces Comfort Index for Hilton Head Island is 7.1 (10=best), which means it is one of the least comfortable places in South Carolina.

The annual BestPlaces Comfort Index for Gaithersburg is 7.3 (10=best), which means it is more comfortable than most places in Maryland.

Today's Weather - Gaithersburg, MD

72°F

Today's Weather - Hilton Head Island, SC

72°F

Average Monthly High / Low (°F)

Hot, Freezing, Rainy, Snowy Days: Gaithersburg / Hilton Head Island

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

July is the hottest month for Hilton Head Island with an average high temperature of 90.8°, which ranks it as cooler than most places in South Carolina. In Hilton Head Island, there are 5 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Hilton Head Island are October, April and May.

January has the coldest nighttime temperatures for Gaithersburg with an average of 25.0°. This is about average compared to other places in Maryland.

January has the coldest nighttime temperatures for Hilton Head Island with an average of 39.2°. This is one of the warmest places in South Carolina.

In Gaithersburg, there are 15.3 days annually when the high temperature is over 90°, which is cooler than most places in Maryland.

In Hilton Head Island, there are 51.5 days annually when the high temperature is over 90°, which is about average compared to other places in South Carolina.

In Gaithersburg, there are 90.3 days annually when the nighttime low temperature falls below freezing, which is about average compared to other places in Maryland.

In Hilton Head Island, 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 Gaithersburg, there are 0.5 days annually when the nighttime low temperature falls below zero°, which is colder than most places in Maryland.

In Hilton Head Island, 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.

May is the wettest month in Gaithersburg with 4.3 inches of rain, and the driest month is February with 2.7 inches. The wettest season is Summer with 27% of yearly precipitation and 21% occurs in Spring, which is the driest season. The annual rainfall of 42.2 inches in Gaithersburg means that it is drier than most places in Maryland.


August is the wettest month in Hilton Head Island with 7.1 inches of rain, and the driest month is May with 2.2 inches. The wettest season is Autumn with 37% of yearly precipitation and 18% occurs in Summer, which is the driest season. The annual rainfall of 48.1 inches in Hilton Head Island means that it is wetter than most places in South Carolina.

May is the rainiest month in Gaithersburg with 11.6 days of rain, and August is the driest month with only 8.2 rainy days. There are 112.7 rainy days annually in Gaithersburg, which is about average compared to other places in Maryland. 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.

August is the rainiest month in Hilton Head Island with 12.3 days of rain, and May is the driest month with only 6.4 rainy days. There are 103.4 rainy days annually in Hilton Head Island, which is about average compared to other places in South Carolina. The rainiest season is Autumn when it rains 32% of the time and the driest is Summer with only a 20% chance of a rainy day.

An annual snowfall of 21.4 inches in Gaithersburg means that it is snowier than most places in Maryland.

An annual snowfall of 0.1 inches in Hilton Head Island means that it is one of the least snowy places in South Carolina.

January is the snowiest month in Gaithersburg with 8.5 inches of snow, and 5 months of the year have significant snowfall.

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