US west braces for fiercest temperatures yet as ‘supercharged’ heatwave arrives

Hottest weather of the year just beginning, warns National Weather Service, as authorities prepare to protect most vulnerable

After days of unrelenting temperatures across much of the region, the American west is bracing for even more intense heat this weekend with more than a third of Americans under extreme heat alerts.

California is facing a powerful heatdome, bringing sweltering conditions expected to build Friday and through the weekend, in central and southern parts of the state. The National Weather Service warned many residents they should prepare for the hottest weather of the year as desert area highs could exceed 120F (48.8C).