‘Corn sweat’ has turned up the heat in the US, pushing temperatures above 100 degrees for nearly 200 million people nationwide.
A thick wave of extreme humidity is expected to hit at least 30 states from the Plains to the East Coast boiling in a massive heat dome this week, with temperatures rising over 100 degrees, and scientists say ‘corn sweat’ is making the heat feel even worse.
As corn reaches its peak growth phase across the Corn Belt, in states like Iowa and Illinois, the fields started acting like steam machines, fueling dangerous heat that could last through the weekend.
They have started pumping thousands of gallons of water per acre into the air each day through a process called evapotranspiration, or corn sweat. That moisture gets trapped under the heat dome, turning the region into a huge sauna.
That heat dome is like a hot air bubble covering an area and trapping heat like a lid on a pot, keeping cooler air and rainstorms out. This makes everything underneath get hotter and hotter, with no way to cool down.
Officials warned that the heat index is expected to reach 110 to 115 degrees in parts of Missouri, Illinois, Iowa, and Indiana.
Major Midwest cities like Kansas City, Des Moines, and Chicago are all under heat watches or warnings through the night, as meteorologists have said the air will stay thick and damp even after the sun sets.
Justin Glisan, an Iowa State University climatologist, said: ‘The phenomenon as being thick and oppressive, particularly if there is no wind, like being fully clothed in a sauna or steam room.’
Corn is pushing temperatures above 100 degrees for nearly 200 million people nationwide
Officials have released an extreme heat warning for areas like the mid-Mississippi Valley Tuesday
According to AccuWeather, more than 200 million people across 37 states will experience the triple-digit heat wave by Friday.
Officials have issued extreme heat alerts for the Mississippi Valley, while the entire Chicago area is under an extreme heat watch through Thursday.
This week, humidity from cornfields has intensified the already severe heat dome, extending from Texas to the Great Lakes.
Over 100 cities are expected to challenge overnight heat records, raising serious risks for heat stress, especially where there is no air conditioning.
The timing of this summer scorcher is no coincidence, as it coincides with the blossoming period of the corn plant. In Iowa alone, corn is planted across millions of acres.
On Thursday and Friday, the heat dome will expand further east, covering the regions that rarely see this level of heat and humidity, especially New England and parts of the Northeast.
In Maine, where summer temperature usually stay in the 70s or low 80s, it could reach the 90s by Friday. Portland is most likely to hit 94 degrees, but humidity will make it feels live over 100 Fahrenheit.
Boston will also get very hot, with temperatures near 100 when you factor in the moisture in the air. Even cities near the coast would not be safe from the heat.
In the Corn Belt, the combo of moist soil, and nonstop sun is making conditions unbearable.
Meteorologists say this heat will be short but strong. It’s not like the long-lasting heat in the Plains, but it still could cause problems.
The heat comes from moisture moving east, mostly from the Midwest’s corn fields, which release a lot of water vapor into the air. This makes the air feel even hotter.
New York City will see some of its hottest days this month with highs in the mid-90s and nights staying warm near 80 degrees.
Many cities in the South and Midwest will also stay hot at night, giving little relief from the heat. Places like Little Rock and Jackson could see nighttime lows only reach the 80s.
Corn in states like Iowa, Illinois, and Indiana is at a stage where it releases lots of moisture, which adds to the humidity spreading east.
Washington, DC, will hit 97 degrees Friday, but it will feel hotter, between 105 and 110 because of the extra humidity coming from the South and Midwest.
According to AccuWeather, Dallas will reach over 100 degrees, and Houston and San Antonio will stay in the triple digits.
By Friday, the heat dome will expand into the Northeast and Mid-Atlantic
Forecasters say the Central Plains, including Kansas and Nebraska, could shift from humid to dangerously dry by mid-August.
The heat will worsen with dry ground, pushing temperatures from the upper 90s to 100, with some areas possibly hitting 110 degrees Fahrenheit.
AccuWeather Senior Meteorologist Chad Merrill said: ‘The bottom line is that this has the look of a long-lasting heat wave with limited rainfall.’
The Corn Belt is not in a drought right now, but that could change. As the ground dries under this heat dome, less water will evaporate to cool the air, and actual temperatures will rise even more. Some areas could climb to 110 degrees or more.
Even tropical moisture from the Gulf would not help much. High pressure is blocking it from moving north in most places, and whatever rain does fall likely would not be enough to cut the heat.
