(NEW YORK) — Heat is the No. 1 weather-related killer — and it’s heading to the most densely populated part of America for a prolonged period.
A heat wave forecast to envelop the Midwest and the Northeast with triple-digit weather is expected to arrive on the heels of the first official day of summer.
But before the sizzle, the country’s midsection and much of the East Coast will have to endure at least a couple of days of severe weather.
Over the next two days, more than 120 million people are under the threat for severe storms from the Midwest to the East Coast.
The risk for severe weather — which could produce damaging wind, tornadoes, large hail and possible flash flooding — is at a level 3 out of 5 on Wednesday from Michigan to Missouri, including the cities of Indianapolis and Louisville. Meanwhile, the risk of severe weather for the cities of Chicago, Detroit, Cincinnati, Nashville and Texarkana is at a level 2 out of 5 on Wednesday.
Storms are expected to reach Chicago around the lunch hour on Wednesday and move into Indianapolis, Detroit and Cincinnati later in the afternoon. Nashville and Texarkana are expected to see severe weather Wednesday evening and and overnight.
On Thursday, severe weather is expected to move to the East Coast from North Carolina to Vermont and include Washington, D.C., and New York City.
Out West, extreme heat warnings are in place for Thursday and Friday from Phoenix to Las Vegas, where temperatures could soar to 115 over the region.
The hot weather in the West is also expected to elevate the risk of fire danger from Nevada to Colorado. The National Weather Service has issued red flag warnings for Wednesday afternoon and into the evening for northwest Colorado and northeast Utah, where 35 mph gusts and single-digit humidity could allow fire to spark and spread rapidly.
By week’s end, daily high temperature records could fall in parts of the West, where places like Denver could top 100 degrees.
Bracing for the season’s first heat wave
Starting on Sunday, the hot weather will invade the Midwest and parts of the Southeast. The heat index is forecast to make it feel like more than 100 degrees in Chicago, Louisville and Nashville.
By Monday, record-breaking daily high temperatures are expected to be widespread across the Mid-Atlantic and Northeast, with highs from the mid-90s to the low-100s.
High humidity will make conditions more stifling for tens of millions of people. The heat index, a measure of what the temperature feels like, is expected to rise to the low to mid-100s in New York City, Boston and Washington, D.C., on Monday and extend into next week.
During the heat wave, nighttime temperatures are expected to only drop into the 70s, meaning that without adequate air conditioning this heat wave will be extremely dangerous for many Americans.
The dangerous heat in the Northeast is not expected to subside until late next week, when clouds and rain will move into the region.
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