A Sweltering Heat Dome Is Pummeling the Middle of the US. Here's What That Means
The NWS has issued a bulletin warning that 100-degree temperatures will likely hit residents in the middle of the US today. The cause for that thermometer spike is a growing heat dome in the Mississippi Valley that should expand to the northeast by the end of the week, potentially affecting more than 100 million people, per Accuweather.
If "heat dome" is a new term for you, keep reading and I'll break down what it means and what causes it. For more help this summer, check out CNET's top 10 hacks for keeping your home cool in the summer or learn how to recognize the early signs of heatstroke.
What is a heat dome?
Think of a heat dome as similar to putting a lid on a pot or a frying pan while cooking something, Alex Lamers of the National Weather Service told NPR.
A heat dome is what happens when a high-pressure system lingers, causing hot air to become trapped under it, resulting in prolonged temperature spikes. Just like how putting a lid on a pot or pan traps the heat and cooks the food faster. Except in this case, the food is you and me.
This is made worse by the fact that high pressure systems are known to cause dry weather, which can also contribute to hotter temperatures.
According to the heat map provided on the National Integrated Heat Health Information System's official website, heat risks are elevated for most of the country between the Midwest and Lower Mississippi Valley regions and the East Coast, with eastern North Carolina, central Virginia, the Pittsburgh area, southeast Pennsylvania, southeast Maryland, most of New Jersey and almost all of Delaware being under extreme heat warnings.
In the hardest-hit areas, temperatures may go as high as 115 degrees, while others will hover between 95 and 100 degrees. All around, it's the kind of weather than can make the prospect of a power outage a life-or-death scenario.
How long do heat domes last?
I wish I had better news for you.
Heat domes are known to last anywhere from a few days to a few weeks, depending on how long it takes for the high pressure system in a given region to move on or dissipate.
There's no indication how long the current heat dome will last. Accuweather reports that it could even spread to the western US in early August.
Does climate change make heat domes worse?
Oh, absolutely.
Speaking to Time Magazine for a report on the current heat wave, Bill Gallus, a professor of meteorology at Iowa State University, said that cause-and-effect question was "one of the easier (questions) to answer."
Heat domes, he explained, are one of the more likely consequences of worsening climate change, even more so than other related weather events, such as increased tornadoes and stronger hurricanes.
"There's so many things that are complicated and we can't say for sure what climate change is going to do, such as how many hurricanes or tornadoes we get," Gallus said. "But it is likely that we will have more heat domes and probably hotter temperatures in the heat domes."
How to avoid heat domes
As you might guess from these explanations so far, there's not much to do about a heat dome except get away from it.
This might entail staying inside where it's cool or traveling to another place that isn't suffering under a high-pressure system. Maybe head out to the west coast, where my other CNET colleagues -- whom I am not jealous of and never have been, promise -- insist the weather is positively temperate. Hope you're all having fun out there, guys.
Or hey, maybe try the old summertime standby and go see a movie in a nice air-conditioned theater. CNET's Aaron Pruner calls Superman a "punk rock delight," and that new F1 movie looks pretty neat too
For more weather tips, check out CNET's guide to saving power during summer heat waves.
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