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.