100 degree heat to hit Southern California, sizzling summer to follow

A heat wave is expected to strike Southern California this week with temperatures topping 100 degrees in Los Angeles by Wednesday.

Strong winds are expected to accompany the heat, prompting red flag warnings for increased fire danger.

There will be little relief at the coasts as the weather system brings hot air from the east to the west, heating up beach communities like Santa Monica to over 90 degrees.

It’s expected to be hottest from Tuesday to Friday, with temperatures 15-20 degrees higher than average.

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The spike is caused by a storm system that moved through the Northwest and dumped rain and snow over the Rockies last weekend. When that low pressure system meets a high pressure system  over California – it creates the Santa Ana winds.

“This air with the Santa Anas is moving from the desert over the mountains and as it’s moving down the mountain slope its basically being forced downward and that’s a heating mechanism,” said Eric Boldt at the National Weather Service.

The Santa Ana winds are more common in the months of October and November, though they are not unheard of in May. However, many Southern Californians associate this time of year with cool, cloudy weather – hence the terms “May Gray” and “June Gloom.”

The unseasonably hot weather likely won’t let up. The National Weather Service’s Climate Prediction Center released a report in April predicting a hotter than average summer in Southern California.

Climate Prediction Center director Mike Halpert said the continuing dry weather could make the heat worse because areas that have little soil moisture tend to get hotter.

“When solar radiation comes in if there’s not a lot of moisture for it to evaporate all it can do is heat the air,” he said.

However there could be more winter rains coming to Southern California. The Climate Center has forecast a high likelihood of an El Niño event this year, which heats up surface temperatures in the ocean and typically brings more rain to California.

But Halpert cautioned it’s still too early to know how strong this weather system will be and how much of an impact it will have on precipitation in California.