Extreme weather and wildfire briefing (01/20/2025): Extremely critical wildfire risk event in SoCal

The latest in a recurring series of live, virtual, & interactive "office hours" hosted by Dr. Daniel Swain on various topics related to extreme weather and climate. 01/20/2025 topic: I'll have up-to-the-minute updates on yet another "extremely critical" wildfire risk and potentially damaging event will unfold across southern California on Monday and Tuesday. I'll also discuss the possibility of some rain (!) this coming weekend, and how that might be a mixed blessing with respect to fire risk vs. post-fire debris flow hazards.

[petergarin]

Again, thank you for what you do…it allows people to prepare, and anticipate what’s going on. It quells fear, and allows for constructive action and preparation

[Jen.O]

superior information as usual from you, thank you for this tonight

[Kushy]

Thank you for all the great information and analysis, it is so greatly appreciated and while perhaps there are a few views on Weather West, so many of us spread the word and help educate others. We greatly appreciate your efforts to educate the public!

[Fireweed]

Also, roof sprinklers are like pissing in the wind if the home is in the path of the high winds of a Santa Ana fire. The wind negates the water effect. But on the flanks of the Santa Ana fires, homes may profit from a sprinkler system. But you don't want to contribute to the draining of water available to firefighting resources. Put a pump on your pool with a good hose and nozzle that will reach embers on your roof. Leave your hose charged when you evacuate so firefighters can use it.

[helenhenthorn]

The strongest Santa Ana winds yet recorded occurred in early December 2011 in the towns of Pasadena and Altadena in the San Gabriel Valley which had sustained winds at 97 mph. and gusts up to 167 mph. Palisades and Altadena must have dodged numerous disasters in the past…Central Malibu has had 10 fires in 8 decades that penetrated the town.

[ikofire]

I don't understand why the Low Pressure system is creating high pressure. Is it correct to say the Low pressure system is cold so the air is sinking and moving west because the high pressure system over California is warm so the air is rising and creating a vacuum that the cold air is trying to fill? AND when does the Mountain wave effect come into the picture? this is confusing!!

[helenhenthorn]

“Climate change parching the American west even with-out rainfall deficits” - published in Science Daily Nov, 6 2024. The research found that since 2000, evaporative demand has played a bigger role than reduced precipitation in droughts; evaporation accounted for 61% of the drought's severity, while reduced precipitation accounted for 39%.