Overview

• Nearly 30 million Americans live under heat advisories or extreme heat warnings as a heat dome drives Death Valley toward 121°F and Las Vegas and Phoenix into triple-digit highs
• England has yellow and amber health alerts from the UK Health Security Agency ahead of mid-week temperatures expected to reach the mid-30s °C in southern and central regions
• Meteorologists link the US heat surge to a persistent high-pressure dome and the UK spike to a heat dome fuelled by Tropical Storm Dexter remnants on the jet stream
• UK and US health officials warn that vulnerable groups, particularly the elderly and those with pre-existing conditions, face elevated risks of heat-related illnesses and increased demand on social care services
• Long-range outlooks from the National Weather Service and Met Office indicate that above-normal warmth could continue through late August and into early September