Santa Ana winds may stoke firestorms in California

Just days after the Palisades Fire ripped through parts of Los Angeles and forced mandatory evacuations, a Diablo and Santa Ana wind event is escalating the fire threat across California through the remainder of the week.

AccuWeather meteorologists are warning that dry air, heat, strong winds and abundant fuel are providing the ingredients for ‘critical' fire weather conditions.

The conditions can result in dangerous, fast-moving firestorms where some communities may have little notice to get out of harm's way.

Dramatic news chopper footage showed people fleeing flames on foot and by car in the Pacific Palisades area of Los Angeles as a 40-acre fire ripped through on Monday. The Palisades Fire prompted mandatory evacuations of 200 homes, which were later lifted by the Los Angeles Fire Department (LAFD) on Monday evening. The fire is now 55% contained. However, three first responders and one civilian have been injured in the blaze, according to the LAFD.

During Wednesday night, in a matter of a few hours the Kincade Fire, in Sonoma County, California, erupted and surged to 10,000 acres and prompted evacuations. As of 5 a.m. Thursday, there was no containment of this rapidly moving and expanding wildfire.

More fires of similar nature may erupt into Friday with a focus over Southern California through Friday as winds are forecast to ease in Northern California during Thursday afternoon.

Red flag warnings are currently in effect across portions of Northern and Southern California.

On Wednesday, Pacific Gas and Electric announced lengthy power outages for over 170,000 customers across 17 counties to help mitigate the wildfire risk. The outages went into effect at 2 p.m. local time Wednesday in the Sierra Foothills, 3 p.m. in the North Bay counties, and approximately 1 a.m. Thursday in affected areas of San Mateo and Kern counties, PG&E said.

Officials will inspect de-energized power lines as soon as high winds subside so they can be monitored for damage.

"PG&E will safely restore power in stages as quickly as possible, with the goal of restoring the vast majority of customers within 48 hours after the weather has passed," the company said.

In some cases, the relative humidity will dip to under 10%, while temperatures surge into the 70s, 80s and 90s F. Some locations along the coast can approach 100 during the Santa Ana and Diablo event.

Los Angeles will not escape the heat, which will add to the concerns for existing infernos and any new ones that ignite. The high temperature is expected to climb into the 90s each day into Friday.

"In Northern California, the worst conditions from north to northeast winds will be into Thursday," according to AccuWeather Senior Meteorologist Bob Smerbeck.

"In Southern California, the worst conditions from northeast winds will be from Thursday through Friday," Smerbeck said.

The National Weather Service office in Los Angeles also warned that the fire threat will be 'critical' on Thursday and Friday, tweeting that "very rapid fire spread and extreme fire behavior could threaten life/property," as "very dry fuels" are present.

In most areas of California, winds will average 15-30 mph with frequent gusts between 40 and 60 mph.

AccuWeather Local StormMax™ wind gusts to 80 mph will tend to occur in north- to northeast-facing canyons and passes, as well as over hilltops and ridges.

"The strong winds will be set up by a dip in the jet stream centered over the Four Corners region and an area of high pressure the builds inland from the Pacific Ocean and settles over the Great Basin," according to AccuWeather Chief Video Meteorologist Bernie Rayno.

"The two weather systems will create a strong north to northwest flow of air aloft that will translate down to the surface in the form of gusty winds," Rayno said.

There is no indication of a storm with enough moisture to bring appreciable rain to much of California through the first few days of November.

As a result, the risk of wildfires will exist on a daily basis, while episodes of strong winds will periodically raise that threat to critical levels over the next couple of weeks.

While this is prime wildfire season in California, conditions are being made worse by the extra growth of brush from last winter's rainfall. That brush has dried up as the North American monsoon brought practically no rain to California this summer.

People in fire-prone areas are urged to heed evacuation orders for their community when they are given. As a precaution, have valuable papers and heirlooms packed and ready to go. Remember to take your pets with you.

Use extreme caution with open flames and outdoor power equipment.

Never toss burning cigarettes out of vehicles.

Never park a vehicle over brush as the exhaust system is hot enough to catch that brush on fire.

Make sure tree limbs are not coming in contact with overhead wires. If so, have a professional trim the branches to reduce the risk of sparks as soon as possible.

Be vigilant and immediately report suspicious activity to local police.

Download the free AccuWeather app to see the latest forecast and official National Weather Service fire weather advisories for your region. Keep checking back for updates on AccuWeather.com and stay tuned to the AccuWeather Network on DirecTV, Frontier and Verizon Fios.