Latest news with #IowaStateUniversity


CBS News
9 hours ago
- Climate
- CBS News
Maps show U.S. heat advisories, high temperatures as heat dome moves east
The extreme heat that has baked much of the central United States this week is slowly shifting east ahead of the weekend, forecasters said. More than 130 million Americans across at least 20 states are under heat alerts on Thursday. Parts of the Midwest, including the Corn Belt, have felt the high temperatures for multiple days. Temperatures on Thursday are forecast to be 10 to 15 degrees above average for this time of year with feels-like temperatures over 100 degrees expected in multiple areas. Some parts of the Mississippi Valley will continue to see high temperatures over 90 degrees for a few more days, even as the heat dome moves over parts of the Northeast. A heat dome happens when hot air is trapped over an area due to a persistent high pressure system, William Gallus, a professor of atmospheric science at Iowa State University, said. Heat domes can last for days to weeks and can stretch over multiple states. With extreme heat in the Corn Belt, a region including parts of the Plains and Central Mississippi Valley, a phenomenon known as corn sweat has made the humidity worse, experts said. "There are pores on the bottom side of the leaves," Iowa state climatologist Justin Glisan told CBS News national correspondent Lana Zak. "And that's where oxygen is released, but also water vapor." The process can add up to 10 degrees to the feels-like temperature, Glisan said, because just 1 acre of corn can release as much as 4,000 gallons of water into the air per day. Iowa has around 13 million acres of corn.


Axios
13 hours ago
- Climate
- Axios
Flash floods on the rise in Utah
Flash floods are increasingly common in Utah — a phenomenon consistent with climate change. The big picture: Nationally, flash flood warnings have set a new record this year, Axios' Alex Fitzpatrick reports. By the numbers: By rolling five-year averages, Utah's flash flood count rose from 14 in 2000 to almost 45 in 2021, per Utah health officials. Warnings are also trending up, with 14 so far this year from Salt Lake's National Weather Service office, which covers most of Utah, according to a tracker at Iowa State University's Iowa Environmental Mesonet. That's more than the entire year in 1986, the first year for which data was available — and Utah's monsoon season is just beginning. Context: Climate change"is supercharging the water cycle," sparking heavier precipitation extremes and related flood risks, according to Climate Central, a climate research group. The intrigue: The state historically has the nation's least intense rainstorms, per federal weather data — but in southern Utah, a little water can create deadly floods. How it works: "Bare sandstone and scarce vegetation do little to soak up rain. Instead, muddy waterfalls cascade over the cliffs," Capitol Reef National Park explains in a warning to visitors. With just a half-inch of rain in an hour, "dry washes can fill with rushing water, several feet deep, carrying large rocks, logs and debris." Flashback: In 2015, a single storm caused flash floods that killed 21 people in southern Utah — the state's deadliest storm since federal weather analysts began collecting data in 1950. Seven canyoneers died in Zion National Park, while 13 people — three women and 10 children — drowned when a van was swept away near Hildale. A Hurricane motorist died in floods from the same storm. The latest: The Washington Post reported last week that the development of a tool aiming to predict how rising temperatures will impact extreme rainfall frequency had been delayed amid a U.S. Commerce Department review.


Axios
3 days ago
- Climate
- Axios
Colorado sees fewest flash flood warnings since 2008
Despite a record-setting year for flash flood warnings nationwide, Colorado is seeing its quietest flood season since 2008, per an Axios Denver analysis of data from Iowa State University's Iowa Environmental Mesonet. By the numbers: As of Monday, the National Weather Service has issued 24 flash flood warnings in Colorado so far in 2025. That's down 48% from this time last year — and a dramatic 82% drop from 2023, when the state had already recorded 131 flash flood warnings. Zoom in: El Paso County leads the state with six warnings this year. Larimer and Pueblo counties follow with three each. The intrigue: Denver hasn't had any flood alerts this year. Still, the city shattered a 75-year rainfall record on March 26, logging 1.39 inches in a single day, per FOX31. The big picture: Scientists say climate change supercharges rainstorms by warming the atmosphere, allowing it to hold and dump more water. But that doesn't mean every region sees more rain every year.


Axios
3 days ago
- Climate
- Axios
Flash flood warnings surge in New Orleans metro
The National Weather Service in New Orleans is having one of its more active years in terms of flash flood warnings since 1987. The big picture: Meteorologists at the office have issued 41 warnings so far this year, according to a tracker at Iowa State University's Iowa Environmental Mesonet. Flash flood warnings are issued when such an event is imminent or already occurring. Several warnings came last week during the tropical system, while others were in April, when a rainstorm dumped more than 6 inches on the West Bank. The totals are for the office's entire coverage region, which includes part of south Mississippi. By the numbers: New Orleans has had 40.89 inches of rain as of Friday morning, which is nearly 5 inches above normal, NWS data shows. Between the lines: Mike Efferson, who has been a meteorologist at the local NWS office since 2008, tells Axios New Orleans he's noticed a change in culture since the 2016 floods in Baton Rouge. Meteorologists are now more proactive and cognizant about the potential impacts of storms, which leads to more warnings, he says. "Society in general is taking flooding more seriously," he says, mentioning how there are more preemptive school closures for severe weather than 30 years ago. Meanwhile, rainstorms in New Orleans are getting more intense, according to data from Climate Central. Hourly rainfall intensity increased 8.7% between 1970 and 2024, writes Axios' Chelsea Brasted. Climate change can amplify rainstorms, as warmer air can hold more water. Zoom out: Nationally, NWS offices have issued a record number of year-to-date flash flood warnings in 2025, according to a tracker at Iowa State University's Iowa Environmental Mesonet.


Axios
7 days ago
- Climate
- Axios
Detroit avoids flash floods while storms batter other cities
Storms sweeping through the U.S. this summer have dumped intense rain on cities across the country, but severe flash floods have mostly missed Metro Detroit. The big picture: Scientists who spoke to Axios say the deadly floods in Texas that killed more than 130 people underscores the risk that climate change can worsen extreme rainfall events. By the numbers: NWS offices issued 3,160 flash flood warnings nationwide this year through July 16, according to a tracker at Iowa State University's Iowa Environmental Mesonet. That's the most for that period in any year since records began in 1986. Zoom in: Metro Detroit has had only a handful of flash flood warnings this year. Wayne County has had zero warnings, Macomb has had two and Oakland County one, according to Iowa Environmental Mesonet's data. Context: Flash floods are sudden and violent, and can develop in minutes or hours. Warnings are issued when a flash flood is imminent or occurring.