A particularly dangerous situation red flag warning is in place from noon Monday to 10 a.m. PT Tuesday for a large portion of Ventura and Los Angeles counties.

Monday's red-flag warning is a PDS, which stands for "particularly dangerous situation." But what does that mean? An NWS meteorologist explains.

The NWS has issued a "Particularly Dangerous Situation" Red Flag Warning for Southern California, effective until 10 a.m. Tuesday, with a fire weather watch continuing from Tuesday evening through Thursday evening due to powerful Santa Ana winds.

NWS' 3:40 a.m. advisory indicates winds were blowing northeast at speeds between 25 to 35 mph, with gusts up to 60 mph.

As firefighters struggle to gain control of massive and deadly wildfires that are raging across parts of the Los Angeles area, the region is once again bracing for the potential of new fires and for current ones to intensify as a new storm system heads for the state.

"If fire ignition occurs, conditions are favorable for very rapid fire spread and extreme fire behavior," the NWS warns.

Red flag criteria is generally when relative humidity is at 15% or less, combined with sustained winds and/or gusts of 25 mph or greater. Both of these conditions must occur simultaneously for at least 3 hours in a 12 hour period, according to the NWS.

Here's a guide to understanding "particularly dangerous situation" red flag warnings, containment, and other terms related to the devastating fires that have left much of the LA area in ruins.

A red flag warning has been issued for the Inland Empire and some cities in the Coachella Valley as strong gusty winds and low humidity are expected early next week. The warning is in effect from 10 a.

Californians in the greater Los Angeles area have been on edge due to high winds and dry conditions. The Palisades and Eaton fires have killed at least 25 and destroyed thousands of homes.

Cal Fire crews are responding to the scene of a brush fire in Ramona that broke out early Tuesday morning, threatening at least one structure.

Two major fires are still uncontained in the Los Angeles area with red flag warnings issued for Monday, meaning powerful Santa Ana winds will make conditions hard for crews to fight already devastating blazes.