cc @rschumacher.cloud

I spent around an hour talking about the formation (and history) of tule fog and associated temperature inversions in this YouTube livestream, which was recorded (like all of my livestreams!). I'll probably discuss again more briefly in tomorrow's new livestream too. www.youtube.com/live/P-FTpZd...

It's pretty wild. While wintertime temperature inversions are common in more moderate form, I'm not sure I've ever seen such a prolonged period of very cold daytime temperatures confined to the Central Valley (& SF North Bay) while immediately surrounding slopes see sustained record warmth for days!

Mid-PM temps within a few hundred feet of sea level in Central Valley (low 40s F) quickly rise to (low 70s F) just 2,000ft up in surrounding slopes. That's an inversion magnitude of ~30F/2,000ft! Amazingly, airmass atop fog layer is *record warm* despite damp chill right at sfc.

That is only part of the problem! The fundamental one is that drought and fuel moisture are excluded *entirely.* Then, the statistical technique used to downscale apparently *amplifies* the issue from paper above, not reduces. So...quite a big issue overall.

I am sorry that some images continue to appear (especially satellite ones, alas!) with extremely low/pixelated resolution on Bluesky. If anyone knows the devs, it would be really really awesome to finally address this! (Same goes for animated custom gifs, often used in science visualizations.) :)

This flood event will also extend into NW Oregon and SW British Columbia, though WA will likely be worst-hit. Major impacts and significant inundation/damage is possible, as are significant landslides. Additional warm rain on horizon through late Dec. #WAwx #BCstorm #ORwx [3/3]

It sure is clumsy! But...what else is new.

This flood event will also extend into NW Oregon and SW British Columbia, though WA will likely be worst-hit. Major impacts and significant inundation/damage is possible, as are significant landslides. Additional warm rain on horizon through late Dec. #WAwx #BCstorm #ORwx [3/3]

On Wednesday, widespread heavy rain & very high snow levels (7,000-9,000 feet) will cause enormous runoff into already swollen rivers. Widespread moderate to major flood is likely, with some rivers expected to experience *record* flooding (esp. Skagit & Snohomish). #WAwx [2/3]