SOME 130 million people have faced or are under threat from dangerously high temperatures during a long-running heat wave that has broken records in the western United States.

Forecasters warned that temperatures are expected to rise even further across the country this week, with wildfires spreading in California.

Ukiah, north of San Francisco, hit 47°C on Saturday, equalling its all-time high. Livermore, to the east of the west-coast city, set a new record of 43.8°C.

Las Vegas equalled its record of 46°C last reached in 2007, while Phoenix topped out at 45.5°C.

“A dangerous and historic heatwave is just getting started across the area, with temperatures expected to peak during the Sunday-Wednesday time frame,” the National Weather Service in Las Vegas said.

Meteorologists predicted that temperatures will be near daily records in the region through the coming week, with lower desert highs reaching 46.1 to 48.8°C.

The eastern US was also bracing for more heat: Baltimore and other parts of Maryland have been warned temperatures could  hit 43°C, forecasters said.