Summer Weather Fountain Valley: Fire Weather In OC Mountains

FOUNTAIN VALLEY, CA — The National Weather Service announced elevated fire weather conditions late Wednesday through Thursday across inland Orange County, in mountains and passes. This is due to strong westerly winds and low humidity, they said in a recent release.

"A high pressure aloft will maintain fair skies and warm to hot days across the region through Tuesday, except at the immediate coast," the NWS reported. "There, a shallow marine layer will keep the days cooler with areas of fog and low clouds at times."

Conditions at the coast will not be as dry, with onshore breezes expected in the afternoon all week.

The ridge of high pressure is expected to break down midweek, as a broad low pressure trough develops over the western United States, NWS said. This will give strength to that blissful breeze off the ocean.

With the strengthening onshore flow comes a deepening marine layer with progressively higher humidity and cooler weather. That marine layer will deepen and spread far inland, to the coastal foothills and valleys.

Expect a cool day on Friday, as daytime temperatures will be approximately 15 degrees cooler than Monday.

Westerly winds will increase midweek and become strong and gusty through the passes and into the deserts, but it will be short-lived as warmer days return next week.

In Orange County Coastal cities of Seal Beach, Huntington Beach, Costa Mesa, Newport Beach, Laguna Beach, Dana Point, and San Clemente expect mostly clear Monday, patchy fog overnight and lows of 56 degrees.

Tuesday, partly cloudy and patchy fog in the morning, with highs from 68-78 degrees. Expect the fog to return overnight with lows in the 50s.

Wednesday, partly cloudy, patchy fog parting to sunny skies with highs in the upper 60s. Fog returns Wednesday night, lows in the 50s.

Thursday, expect mostly cloudy skies, patchy fog in the morning and highs in the 60s at the coast. Thursday night, mostly cloudy, patchy fog with lows in the 50s.

Friday and Saturday, expect partly cloudy skies and highs in the mid 60s as that trough of low pressure returns. The weekend should be cooler, with clouds and sun, highs in the mid 60s, lows in the 50s.

Sunday, weather warms to 7o, partly cloudy and patchy fog.

Orange County cities of Lake Forest, Mission Viejo, Rancho Santa Margarita, Aliso Viejo, San Juan Capistrano, Fountain Valley can expect mostly clear skies on Monday night, with patchy fog after midnight, lows in the mid to low 50s.

Tuesday and Wednesday, expect clouds parting to sun, patchy a.m. fog, with temperatures ranging from 77 to 87 degrees. Overnight, expect fog to return after midnight, with lows in the upper 50s.

Thursday and Friday, partly cloudy in the morning with a patchy marine layer, highs in the upper 60s, low temps in the 50s overnight, with patchy fog returning.

Saturday and Sunday, a slight warm-up is in store, as daytime temperatures hover in the lower to mid-70s, lows in the 50s.

Orange County mountain areas will see early week temperatures in the high 80s to low 90s, low humidity and winds gusting at 25 miles per hour Monday and Tuesday afternoon and evening.

Wednesday will not be as warm with mostly sunny skies, highs in the upper 70s and lows in the 50s.

Thursday and Friday, temperatures drop by 10 degrees to highs in the low 60s with patchy fog returning overnight and lows in the 50s.

Expect mostly clear skies on Friday night.