2025 Compare Climate & Weather:
Sioux City, IA vs Waltham, MA

Highlights

On average, there are 197 sunny days per year in Waltham. Sioux City averages 210 sunny days per year. The US average is 205 sunny days.

Waltham, Massachusetts gets 47.7 inches of rain, on average, per year. Sioux City, Iowa gets 29.5 inches of rain, on average, per year. The US average is 38.1 inches of rain per year.

Waltham averages 50.2 inches of snow per year. Sioux City averages 32.3 inches of snow per year. The US average is 27.8 inches of snow per year.

Weather Highlights

Waltham, Massachusetts
Summer High: the July high is around 82.9 degrees
Winter Low: the January low is 17.1
Rain: averages 47.7 inches of rain a year
Snow: averages 50.2 inches of snow a year

Sioux City, Iowa
Summer High: the July high is around 85.5 degrees
Winter Low: the January low is 9.6
Rain: averages 29.5 inches of rain a year
Snow: averages 32.3 inches of snow a year

BestPlaces Comfort Index

The annual BestPlaces Comfort Index for Waltham is 6.9 (10=best), which means it is about average compared to other places in Massachusetts.

The annual BestPlaces Comfort Index for Sioux City is 7.0 (10=best), which means it is more comfortable than most places in Iowa.

Today's Weather - Sioux City, IA

67°F

Today's Weather - Waltham, MA

48°F

Average Monthly High / Low (°F)

Hot, Freezing, Rainy, Snowy Days: Sioux City / Waltham

July is the hottest month for Sioux City with an average high temperature of 85.5°, which ranks it as warmer than most places in Iowa. In Sioux City, there are 4 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Sioux City are September, June and August.

July is the hottest month for Waltham with an average high temperature of 82.9°, which ranks it as warmer than most places in Massachusetts. In Waltham, there are 4 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Waltham are June, August and September.

January has the coldest nighttime temperatures for Sioux City with an average of 9.6°. This is about average compared to other places in Iowa.

January has the coldest nighttime temperatures for Waltham with an average of 17.1°. This is about average compared to other places in Massachusetts.

In Sioux City, there are 19.8 days annually when the high temperature is over 90°, which is one of the hottest places in Iowa.

In Waltham, there are 9.9 days annually when the high temperature is over 90°, which is hotter than most places in Massachusetts.

In Sioux City, there are 155.6 days annually when the nighttime low temperature falls below freezing, which is colder than most places in Iowa.

In Waltham, there are 129.8 days annually when the nighttime low temperature falls below freezing, which is about average compared to other places in Massachusetts.

In Sioux City, there are 18.9 days annually when the nighttime low temperature falls below zero°, which is about average compared to other places in Iowa.

In Waltham, there are 3.1 days annually when the nighttime low temperature falls below zero°, which is colder than most places in Massachusetts.

June is the wettest month in Sioux City with 4.1 inches of rain, and the driest month is February with 0.7 inches. The wettest season is Autumn with 37% of yearly precipitation and 8% occurs in Spring, which is the driest season. The annual rainfall of 29.5 inches in Sioux City means that it is one of the driest places in Iowa.


March is the wettest month in Waltham with 4.4 inches of rain, and the driest month is February with 3.3 inches. The wettest season is Summer with 26% of yearly precipitation and 23% occurs in Spring, which is the driest season. The annual rainfall of 47.7 inches in Waltham means that it is about average compared to other places in Massachusetts.

May is the rainiest month in Sioux City with 10.3 days of rain, and February is the driest month with only 4.1 rainy days. There are 83.7 rainy days annually in Sioux City, which is one of the least rainy places in Iowa. 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 Waltham with 12.8 days of rain, and September is the driest month with only 9.2 rainy days. There are 130.6 rainy days annually in Waltham, which is rainier than most places in Massachusetts. The rainiest season is Summer when it rains 28% of the time and the driest is Winter with only a 24% chance of a rainy day.

An annual snowfall of 32.3 inches in Sioux City means that it is snowier than most places in Iowa.

An annual snowfall of 50.2 inches in Waltham means that it is snowier than most places in Massachusetts.

December is the snowiest month in Sioux City with 7.3 inches of snow, and 6 months of the year have significant snowfall.

January is the snowiest month in Waltham with 14.9 inches of snow, and 6 months of the year have significant snowfall.