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Environment & Climate

Heat dome forecast to bring extreme temperatures to South-West US

The National Weather Service warns that over 45 million people face hazardous heat, with highs reaching up to 115°F through early September.

The short version

  • A strong upper-level high-pressure system is expected to trap hot air across the south-western and south-central U.S., driving daytime temperatures up to 115°F.
  • More than 45 million people across the region are facing Extreme HeatRisk warnings, with minimal overnight cooling expected.
  • Localities including Los Angeles are opening cooling centers, while officials advise residents to limit outdoor activity and take precautions against heat-related illness.

Key facts

  • The National Weather Service forecasts that a heat dome will affect over 45 million people in the south-western U.S. through late August and early September.[The Guardian]
  • Daytime temperatures are projected to reach between 100°F and 110°F in the Southern Plains and up to 115°F in portions of the South-West.[The Guardian]
  • The heat wave is accompanied by monsoonal moisture bringing scattered heavy showers and thunderstorms to parts of the South-West, Rocky Mountains, and Plains.[The Guardian]
  • Municipalities such as Los Angeles are opening dedicated cooling centers to assist residents without adequate air conditioning.[The Guardian]

What remains uncertain

  • The precise extent to which existing temperature records will be tied or broken remains subject to daily local weather variations.[The Guardian]

Sources