Just what the US didn't want: Another heat dome. The same type of system that roasted the Northwest at the end of June is in play this week, and it’s covering more ground. Temperatures are surging upward again, and the highs are predicted to be at least 10 degrees hotter than average in the Lower 48, per the Washington Post. By midweek, the heat dome should stretch across the country, from the Pacific to Appalachia. The Southwest has some moist clouds shading it, and New England will likely avoid the hottest temperatures. But the Midwest and Great Lakes are likely to see hot weather, with little relief at night, and strong thunderstorms.
And the heat surging through the middle of the country will bring humidity, too, making it feel even more oppressive, CNN reports. Last month’s record heat killed more than 100 people in Oregon alone, notes USA Today. It also didn't help the wildfire situation—more than 80 fires have now burned through more than a million acres, Slate reports. Heat domes occur when high pressure traps warmer air near the ground and diverts cooling clouds away from the hotter area, per NBC News. (Read more heat wave stories.)