With summer-like temperatures and gusty winds forecast, a red-flag warning is in effect for much of Southern California through Wednesday.

Building high pressure is expected to create an "extended moderate to strong Santa Ana wind event" across Los Angeles and Ventura counties through Wednesday afternoon, with potential gusts of over 60 mph in the mountains and up to 50 mph in the valleys, according to the National Weather Service.

The high winds and low humidity, along with built-up stores of dry fuel and a lack of rain, prompted the weather service to issue the red-flag warning -- meaning critical fire conditions -- for all of Ventura County and most of Los Angeles County, according to the Los Angeles Times.

Temperatures are expected to increase as the week wears on, with the potential to set records. Downtown highs should hit the high 70s on Monday, and then the mid-80s through Thursday, threatening the record of 85 degrees for Jan. 15 that was set in 2009. 

Lancaster set a record Saturday with a high of 74, breaking the Jan. 11 record of 71 set in 1999.

High temperatures are expected to drop back into the 70s on Friday, according to the weather service.

--Los Angeles Times staff