Record-Breaking October Heat Wave Refuses To Let Go Of Los Angeles

LOS ANGELES, CA — A historic October heat wave continued to grip Los Angeles and much of Southern California Wednesday after downtown Los Angeles endured an unprecedented fifth consecutive day of triple-digit temperatures and another daily record fell at Hollywood Burbank Airport.

Burbank Airport reached 101 degrees Tuesday, setting a daily record, according to the National Weather Service in Los Angeles. It was the only daily high-temperature record set Tuesday in the Weather Service's Los Angeles forecast area, but followed a string of records broken or tied Monday as the prolonged heat wave baked the region.

Downtown Los Angeles reached 104 degrees Monday, breaking the previous Oct. 5 record of 101, while Woodland Hills hit 106, topping its previous daily record of 105. Long Beach Airport tied its daily record at 104, Los Angeles International Airport tied its record at 101 and Burbank tied its Oct. 5 record at 102, according to the National Weather Service's Los Angeles forecast discussion.

The duration of the heat has been particularly remarkable downtown, where Tuesday became the fifth consecutive day with temperatures reaching at least 100 degrees, extending a new October record. Forecasters said Wednesday morning there was only a 30 percent chance downtown would reach 100 again, meaning the streak will likely end at five days.

The record-setting heat has stretched well beyond Los Angeles County. On Tuesday, Anaheim reached 100 degrees, Vista hit 101, Chula Vista reached 97, Escondido climbed to 105 and Ramona hit 101, all setting daily records, while Alpine tied its record at 100, according to the National Weather Service San Diego record report.

Those records followed an even hotter Monday, when Santa Ana reached 106 degrees, Anaheim hit 104 and Escondido reached 106. San Diego tied its Oct. 5 record at 97, while Oceanside Harbor tied its record at 93.

Heat Finally Begins To Ease

The heat is not finished yet, but relief is finally on the horizon. The dome of high pressure responsible for the prolonged hot spell is weakening as onshore flow increases, beginning a three-day cooling trend. Coastal areas and portions of the valleys south of Point Conception should cool by about 4 degrees Wednesday, although highs will remain mostly in the 90s along the coast and between 98 and 105 degrees in the valleys.

Most areas should cool another 2 to 4 degrees Thursday before a more noticeable drop of 4 to 8 degrees Friday, which forecasters expect will finally eliminate the heat risk. An Extreme Heat Warning remains in effect until 8 p.m. Thursday for the Los Angeles County coast and valleys.

By the weekend, the change could be dramatic. Temperatures are forecast to fall another 5 to 10 degrees Saturday and 4 to 8 degrees Sunday, when coastal and valley communities south of Point Conception may see highs only in the 70s. Sunday temperatures could run 3 to 6 degrees below normal, and locally as much as 8 degrees below normal.

From Record Heat To Possible Rain

The sharp cooldown could be accompanied by another dramatic change: rain.

An early-season upper-level low could interact with moisture from the remnants of Hurricane Rachel, bringing a chance of showers to Los Angeles County Sunday and a broader chance of rain Monday. Forecasters put the chance of thunderstorms Monday at 5 to 10 percent, while eastern Los Angeles County could receive as much as three-quarters of an inch of rain.

Rachel is already affecting the coastline, with southerly swell expected along Los Angeles and Ventura counties and Catalina Island through at least Saturday. A Coastal Flood Advisory remains in effect through 11 p.m. Friday, with the greatest impacts expected around Long Beach's Alamitos Peninsula, Catalina Island and the Malibu-Zuma Beach coast.

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