Record-breaking heat dome growing to cover nearly the entire U.S.

Key Points:

• A massive heat dome is spreading across the United States, shattering March temperature records in 14 states and creating one of the most expansive heat waves in American history, potentially rivaling events in 2012 and 2021.
• The heat dome, caused by high pressure trapping hot air, has led to prolonged record-breaking temperatures, such as Flagstaff, Arizona experiencing 11-12 consecutive days above previous March records.
• Temperatures have reached as high as 44.4°C (112°F) in parts of Arizona and California, breaking the record for the hottest March day in the continental U.S. by 2°C (4°F), with around one-quarter to one-third of continental states nearing record highs.
• Climate scientists attribute the extreme heat to climate change, stating it is "virtually impossible" without human-induced warming, which has increased temperatures by at least 2.6°C (4.7°F), and warn of consequences like earlier snowmelt, increased wildfire risk, and potential water shortages.
• The heat dome is expected to persist until mid-next week before moving on, with meteorologists emphasizing the unusual scale and duration of this event across the U.S.