why is the midwest so humid

Why is the Midwest so humid? The diverse climate characteristics of the Midwest region in the United States are well-known, thanks to its extensive geographical range.

This region stretches from North Dakota in the northern part to Missouri in the southern part, and from Ohio in the eastern part to Nebraska in the west.

While there are various climatic shifts from season to season, the humidity stays on the higher side.

And this makes people ask, “Why is it so humid in the Midwest?”

It is humid in the Midwest due to its geographical location in close proximity to the Gulf of Mexico, the impact of corn fields, and weather patterns. 

More about the Climate in the Midwest

more about the climate in the midwest

In the Midwest, you will notice four distinct seasons, and they all have temperature variations.

For instance:

WinterMidwest winters are cold, windy, and snowy. Minnesota and North Dakota often see subzero temperatures.
SpringSpring temperatures rise slowly, helping vast agricultural lands benefit from the season’s high rains.
SummerSouthern and central regions have hot, humid summers, with heat waves and violent thunderstorms characterizing the season.
FallFall is beautiful with lower temps and changing leaves, and it is usually dry, leading into winter.

Severe weather

severe weather

Tornadoes are a common occurrence in the Midwest, particularly in Tornado Alley, an area encompassing states like:

  • Kansas
  • Nebraska
  • Some regions of Iowa

Severe weather occurrences are typically more frequent during the spring and early summer months


The Midwest’s climate is characterized by its significant humidity levels, especially during the summer season.

The area’s closeness to the Gulf of Mexico enables the northward movement of warm, moisture-filled air, which plays a role in the elevated humidity levels. 

Is the Midwest More Humid than the Gulf Coast?

midwest vs. gulf coast humidity comparison

The Midwest is definitely humid, but Every year, the Gulf Coast takes the crown for its unpleasant humidity.

It happens because dew points in the Gulf Coast sometimes climb to the humid upper 60s and lower 70s during winter and consistently hover in the lower 80s throughout summer.

During the summer months, the Midwest experiences a rise in dew points, reaching the 70s on multiple occasions, as tropical air masses make their way into the region.

Nevertheless, plants release moisture back into the atmosphere through a phenomenon known as evapotranspiration.

Fact: During the height of the growing season in the Midwest, corn fields have the potential to release more than 9,000 gallons of water, making the atmosphere more humid. 

Why Is the Midwest So Humid?

causes of high humidity in the midwest

Renowned for its unpredictable weather patterns, the Midwest is particularly notorious for its summertime humidity.

What is the reason behind the high humidity in the Midwest?

Here are some possible explanations:

The Midwest Geography and Climate

the midwest geography and climate

Known as America’s heartland, the Midwest covers a total of twelve states.

The states that fall under this category are:

The Midwest Region
South DakotaNorth DakotaWisconsinOhio

The area is expansive, including a wide range of terrains.

You can easily discover:

  • Flat plains
  • Undulating hills
  • Dense forests
  • Productive farmland

Every type of landscape possesses its unique microclimate. That is the reason why you will observe differences in weather patterns throughout the Midwest region with high humidity.

Fact: The high humidity creates a sticky sensation in the air, causing it to feel warmer than the recorded temperature.   

Proximity to Large Bodies of Water

proximity to large bodies of water

The importance of the Midwest’s connection to vast water bodies, such as the Gulf of Mexico, cannot be overstated.

This large body of water serves as a significant source of moisture. It plays a crucial role in determining the climate and levels of humidity in the Midwest.

In the summer, the influential winds, commonly called the “Gulf Breezes,” have a notable impact.

The winds begin in the southern region and travel towards the north. As they travel, they bring along the Gulf’s balmy and humid atmosphere.

The atmosphere is filled with water vapor, which is the primary element of humidity. 

An Important Consideration

As the air abundant in moisture makes its way to the Midwest, it scatters and creates a humid ambiance. This leads to the characteristic suffocating, clingy warmth.    

The Influence of the Jet Stream

the influence of the jet stream

The jet stream is a swiftly flowing air current located in the upper atmosphere.

It plays a crucial role in shaping the Midwest region’s weather patterns, including its humidity levels.

It functions as an enormous atmospheric conveyor belt, transferring weather patterns from one region of the nation to another. 

How It All Works with the Gulf of Mexico?

gulf of mexico's role in the process

In the summer season, it is common for the jet stream to shift towards the north, relocating itself above the Midwest region.

The shift holds great importance, as it alters the weather dynamics of the area. A void is created when the jet stream fails to bring cooler and drier air from the west.

This empty space enables the unhindered movement of warm, moist air from the Gulf of Mexico towards the north. Imagine this Gulf air as an enormous, imperceptible moisture cloud.

As this cloud makes its way to the Midwest, it envelops the area with a layer of moisture-filled atmosphere, resulting in elevated humidity levels

An Important Consideration

The placement of the jet stream during summer plays a crucial role in the humidity levels experienced in the Midwest.

By shifting towards the north, this aerial pathway enables the area to experience an influx of damp Gulf air, leading to the occurrence of those sticky, suffocating summer days. 

Lack of Mountain Barriers

lack of mountain barriers

The Midwest is known for its expansive plains and gentle undulations, rather than majestic mountain ranges.

It does not possess the natural obstacles that frequently interrupt the movement of air in different areas.

In regions of the United States that boast prominent mountain ranges, like the Western states, these majestic landforms serve as tangible barriers.

Moisture-laden air from the oceans can be stopped from moving inland, potentially lowering the percentage of humidity.

However, in the Midwest, there are no such obstacles. The absence of mountains enables the humid air from the Gulf of Mexico to flow freely throughout the area.

Therefore, the absence of mountainous barriers in the Midwest contributes significantly to its elevated levels of humidity.

Fact: The unhindered flow of air enables a consistent influx of moisture, resulting in the development of sticky, damp weather conditions. 

The Role of Agriculture

the role of agriculture

The Midwest has gained recognition for its extensive agricultural operations. The landscape is adorned with fields of corn, soybeans, and wheat.

Not only do these crops provide sustenance for the country, but they also serve additional purposes. Additionally, they have an impact on the moisture levels in the area. 

The Impact of Transpiration

Plants emit water vapor into the atmosphere through their foliage. When countless expanses of crops exhibit this behavior, the cumulative effect becomes significant.

the impact of transpiration

Consider corn as a prime illustration. Each day, a solitary cornfield has the ability to emit numerous gallons of water into the atmosphere.

When you consider the immense number of cornfields spread throughout the Midwest, the effect becomes quite substantial.

Throughout the period of plant growth, this extensive process of transpiration has the potential to enhance the moisture levels in the surrounding area. 

Therefore, the crops that characterize the Midwest’s agricultural identity simultaneously play a role in shaping its humid summer weather. 

Impact of Climate Change

Climate change is an issue that affects the entire world, causing various impacts at the local level.

The Midwest is not an exemption. Alterations are occurring that lead to a rise in moisture levels. 

impact of climate change

Climate change is leading to a general increase in the temperatures of our planet. The capacity of warmer air to retain moisture is higher.

The fundamental concept of meteorology is currently unfolding in the Midwest.

As global temperatures rise, the air in the Gulf of Mexico also experiences an increase in temperature.

The heated air collects additional moisture. Upon reaching the Midwest, the level of humidity surpasses its previous state. 

An Important Consideration

level humidity

The level of humidity has the potential to impact various other atmospheric conditions. This phenomenon has the potential to intensify storms and alter precipitation patterns. 

Fact: With climate change, there is an increase in the air's capacity to retain moisture, consequently leading to an increase in humidity every year. 


Why is the Midwest so humid? The humidity in the Midwest is caused by various factors, such as its close proximity to the Gulf of Mexico, the impact of the jet stream, and so on.

Due to the effects of climate change, the problem of humidity is expected to deteriorate, resulting in increasingly oppressive summers.

Gaining knowledge about these elements can assist individuals from the Midwest in getting ready for, and potentially reducing, the impacts of elevated moisture levels.