UPDATE: Red Flag Warning for 'Critical Fire Weather Conditions' Until 6 p.m. Saturday

Update 2:35 p.m. Cal Fire officials in San Diego County have issued tips for residents in fire-prone areas during the current red flag warning through 6 p.m. Saturday Sept. 27.

"The most critical fire weather conditions will occur just west of Banning Pass," the National Weather Service advised at noon today.

"Fire-fighting agencies throughout the state will be on high alert this weekend," Cal Fire Capt. Mike Mohler said in a statement.  "This is the first Red Flag Warning of what is shaping up to be one of the most challenging fire seasons in many years. High winds can turn a spark into a devastating wildfire in just minutes."

During red flag warnings, Cal Fire urges all Californians to exercise extreme caution outdoors in order to prevent wildfires. Fire prevention tips include:

- Don't mow or use a weed-eater to trim dry grass on windy days.

- Never pull over your vehicle in dry grass.

- Never burn landscape debris like leaves or branches on "No Burn Days" or when it's windy.

- Make sure all portable gasoline-powered equipment have spark arresters.

- If campfires are allowed, be sure to extinguish them completely.

Posted 12:50 p.m. The National Weather Service has issued a red flag warning through 6 p.m. Saturday, with the "most critical fire weather conditions" expected just west of the San Gorgonio Pass.

"Strongest winds will be late tonight and Saturday morning . . . near Banning Pass,"  the Weather Service advised at noon Sept. 27.

The lowest humidity levels are expected Saturday, below 10 percent in some areas, with easterly winds around 25 miles per hour, and gusts to 35 mph through and below passes and canyons in inland Orange County, the Santa Ana Mountains and foothills, and the Inland Empire.

"Durations of combined humidity below 15 percent and wind speeds of 25 mph will be up to six hours," the Weather Service advised. "In most of these areas . . . fuels are very dry."

A red flag warning means critical fire weather conditions are either occurring now or will shortly, according to the Weather Service. A combination of strong winds, low relative humidity, and warm temperatures have potential to contribute to extreme fire behavior.