Humid heat is blanketing the eastern U.S. this week, exacerbated by “corn sweat” in the Midwest
Heat and humidity will once again smother the eastern half of the country this week, pushing the heat index to dangerous levels for tens of millions of people. In the Midwest, the humidity will be boosted by a phenomenon called “corn sweat.”
It’s midsummer, so heat and humidity are pretty standard in the wetter eastern half of the country. It’s unlikely this heat wave will break records, but it could still be dangerous, says Bob Oravec, lead forecaster at the National Weather Service’s office in College Park, Md.
On Monday the heat and humidity are centered over the Southeast and along the Gulf Coast. By midweek, they will move northward along the Mississippi Valley and up into the Midwest before they shift toward the mid-Atlantic and Northeast around the end of the week. Highs are expected to be around 95 to 100 degrees Fahrenheit (35 to 38 degrees Celsius) as the heat wave moves along, but the humidity means it could feel closer to 110 degrees F (43 degrees C) in the most affected areas. Large swaths of the eastern U.S. will be in the “major” HeatRisk category, a NWS classification that incorporates heat, humidity and data on when heat-related hospitalizations tend to rise in a given area. Pockets will be in the “extreme” category, the highest on the four-category scale.
Part of the reason for the oppressive humidity is that “the weather pattern has been favorable for wet weather,” Oravec says. “Everything is wet, saturated,” which means there is more evaporation from soil and transpiration from plants. This is particularly true in the Midwest, where huge fields of corn, soybeans and other crops release moisture as the temperature climbs. The process is akin to how humans perspire in the heat, hence the nickname “corn sweat.” “The Midwest is famous for high dew points from the vegetation,” Oravec says.
Plants aside, the phenomenon has serious implications for humans. High humidity and heat raise the risk of heat illness—it is harder for the body to cool itself via sweating because the air is already so full of moisture that perspiration doesn’t evaporate. Those concerns are especially high for at-risk groups such as young children, older adults, those who have various health conditions or take certain medications, people who work outdoors and unhoused people.
Honestly I think he did a really good job as Superman.
It does suck. We get nights that would be fine to open up to except for the humidity
Why do Americans have to claim to have found something out that everyone already knows and give it a dumb name?
The wet bulb temperature, as this is actually called, has been known about for at least a century.
Because that’s not what is happening here. This is talking about the effects of tens of thousands of square miles of corn fields’ contribution to the humidity in the region, not the concept itself…
Heat index is more commonly used and more frequently now in media (hmmm, wonder why?) but I think this is just some intern or AI that ran across a local midwest slang and ran with it to embellish their news story about the current heat wave to fill it out to a larger word count. I’m not from the midwest, so I’ve never heard that before.
Even though heat index is often used, temperature is still the main one talked about, which is fine under normal conditions. But it doesn’t take a very high temperature with high humidity to become very dangerous. Any time I think about this my mind goes back to the first chapter of “Ministry of the Future” and how horrible now already can be for some places, and the future will just expand where that happens.
You’re in America.
