2025 Compare Climate & Weather:
Vermillion, SD vs Longmont, CO

Highlights

On average, there are 247 sunny days per year in Longmont. Vermillion averages 209 sunny days per year. The US average is 205 sunny days.

Longmont, Colorado gets 14.8 inches of rain, on average, per year. Vermillion, South Dakota gets 27.7 inches of rain, on average, per year. The US average is 38.1 inches of rain per year.

Longmont averages 36.4 inches of snow per year. Vermillion averages 31.8 inches of snow per year. The US average is 27.8 inches of snow per year.

Weather Highlights

Longmont, Colorado
Summer High: the July high is around 89.1 degrees
Winter Low: the January low is 12.5
Rain: averages 14.8 inches of rain a year
Snow: averages 36.4 inches of snow a year

Vermillion, South Dakota
Summer High: the July high is around 85.9 degrees
Winter Low: the January low is 9.3
Rain: averages 27.7 inches of rain a year
Snow: averages 31.8 inches of snow a year

BestPlaces Comfort Index

The annual BestPlaces Comfort Index for Longmont is 7.2 (10=best), which means it is more comfortable than most places in Colorado.

The annual BestPlaces Comfort Index for Vermillion is 7.0 (10=best), which means it is one of the most pleasant places in South Dakota.

Today's Weather - Vermillion, SD

80°F

Today's Weather - Longmont, CO

49°F

Average Monthly High / Low (°F)

Hot, Freezing, Rainy, Snowy Days: Vermillion / Longmont

July is the hottest month for Vermillion with an average high temperature of 85.9°, which ranks it as warmer than most places in South Dakota. In Vermillion, there are 4 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Vermillion are September, June and May.

July is the hottest month for Longmont with an average high temperature of 89.1°, which ranks it as warmer than most places in Colorado. In Longmont, there are 3 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Longmont are September, June and May.

January has the coldest nighttime temperatures for Vermillion with an average of 9.3°. This is warmer than most places in South Dakota.

December has the coldest nighttime temperatures for Longmont with an average of 12.2°. This is colder than most places in Colorado.

In Vermillion, there are 23.6 days annually when the high temperature is over 90°, which is hotter than most places in South Dakota.

In Longmont, there are 37.5 days annually when the high temperature is over 90°, which is hotter than most places in Colorado.

In Vermillion, there are 155.9 days annually when the nighttime low temperature falls below freezing, which is warmer than most places in South Dakota.

In Longmont, there are 178.8 days annually when the nighttime low temperature falls below freezing, which is colder than most places in Colorado.

In Vermillion, there are 20.4 days annually when the nighttime low temperature falls below zero°, which is warmer than most places in South Dakota.

In Longmont, there are 11.2 days annually when the nighttime low temperature falls below zero°, which is colder than most places in Colorado.

June is the wettest month in Vermillion with 4.2 inches of rain, and the driest month is January with 0.5 inches. The wettest season is Autumn with 37% of yearly precipitation and 6% occurs in Spring, which is the driest season. The annual rainfall of 27.7 inches in Vermillion means that it is one of the wettest places in South Dakota.


May is the wettest month in Longmont with 2.3 inches of rain, and the driest month is February with 0.4 inches. The wettest season is Summer with 38% of yearly precipitation and 10% occurs in Spring, which is the driest season. The annual rainfall of 14.8 inches in Longmont means that it is drier than most places in Colorado.

May is the rainiest month in Vermillion with 10.4 days of rain, and February is the driest month with only 3.8 rainy days. There are 79.5 rainy days annually in Vermillion, which is about average compared to other places in South Dakota. The rainiest season is Summer when it rains 31% of the time and the driest is Spring with only a 16% chance of a rainy day.

May is the rainiest month in Longmont with 9.8 days of rain, and January is the driest month with only 4.2 rainy days. There are 79.2 rainy days annually in Longmont, which is about average compared to other places in Colorado. The rainiest season is Summer when it rains 31% of the time and the driest is Spring with only a 17% chance of a rainy day.

An annual snowfall of 31.8 inches in Vermillion means that it is one of the least snowy places in South Dakota.

An annual snowfall of 36.4 inches in Longmont means that it is less snowy than most places in Colorado.

December is the snowiest month in Vermillion with 6.6 inches of snow, and 7 months of the year have significant snowfall.

March is the snowiest month in Longmont with 7.3 inches of snow, and 7 months of the year have significant snowfall.