Overview

• More than 130 million Americans are under National Weather Service heat warnings and advisories from the Lower Mississippi Valley through the Mid-Atlantic as heat-index values climb into the triple digits.
• Localized thunderstorms offer sporadic relief, but overnight lows stubbornly above 75°F are limiting nighttime cooling and elevating the risk of heat-related illnesses.
• Authorities urge residents to stay hydrated, seek air-conditioned shelter, and monitor at-risk individuals as NWS HeatRisk alerts signal widespread major or extreme heat danger.
• Climate Central analysis finds that fossil fuel–driven warming has made this week’s heat dome at least three times more likely for nearly 160 million people in the United States.
• UK forecasts from the Met Office and WX Charts indicate a building high-pressure ridge could deliver 31°C–33°C hot spells across southern England around August 5–8, threatening a fourth heatwave.