Brutal heatwave descends on U.S. West, prompting fire warnings

A heatwave already punishing parts of the U.S. Southwest on Monday (June 14) was expected to move into California this week, prompting the forecasters to warn of health and fire dangers.

Meteorologists say a high-pressure ridge that built over southwestern deserts over the past few days is responsible for the unusually blistering heat this early in the year.

California saw balmy weather on Monday, with temperatures in the upper 80s and low 90s Fahrenheit (30-35°C), but forecasts called for warming on Tuesday (June 15), spiking into the triple digits by Thursday (June 17) and lasting several days.

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The National Weather Service issued an excessive heat warning for parts of southwest Arizona, including Phoenix, on Monday, predicting "dangerously hot conditions" at last through Saturday.

(Temperatures are in Celsius)

California's dry winter left forests and brush parched, prompting worries that the heatwave could touch off wildfires.

Wildfires scorched more than 6,500 square miles (17,000 square km) of land in 2020, destroying hundreds of Californian homes during a particularly fierce fire season.

The baking weather could also strain California's power grid as residents crank up air conditioning units across the state.

Experts say the heatwave forecast for this week, brought on by the early high-pressure system, could not be blamed directly on climate change.

As of June 1, a quarter of the area of the western United States is experiencing an exceptional drought, which is more than twice the area of any period at that level in the last decade. This level of drought can bring about widespread crop and pasture loss, fire risk and water shortages that result in water emergencies.