A strong storm offshore will cause hazardous conditions along the coast this weekend. 🧵 Satellite data confirms storm force winds (60 mph) and very high seas over 40 ft associated with this storm.

🌇The sun will set at 4:51 pm in San Francisco this evening. That's the earliest of the year. 🤔Why doesn't that occur on the Winter Solstice? 2 reasons. The Earth's elliptical orbit around the sun, and the rotational axis tilt.

Ok night owls🦉let's talk about the recent tsunami warning🌊We don't get these alerts very often and there are lot of questions, frustration, and even some anger about how it all unfolded. We'll go over the history, science and warning process👇 How common are tsunami warnings in California? There are several types of tsunami alerts, and warnings are the most critical.

Okay night owls, get your science hats on! Looks like cloud seeding won the poll for tonight's lesson.

We will focus on glaciogenic cloud seeding. Don't worry, we'll go over what 'glaciogenic' means in the lesson.

This might be a long one, so gear up for some learning!
🤓🧪🧵

https://twitter.com/NWSBayArea/status/1823344773429953000

First, the NWS is not currently directing any cloud seeding projects. All current projects in the US are mostly sponsored by universities, public utilities, and private industry. Some of us have worked on these projects before coming to the NWS, and we just think it's fascinating

🤓 The 850 mb temperature reached 30.2 C this evening 🌡️. That's in the top 0.01% of historical observations. 🧵1/4 850 mb is roughly 5,000 ft. We launch weather balloons🎈 from Oakland twice a day to get atmospheric soundings of temp, humidity and wind. There have been over 56,000 going back to 1948. This evening's observation ranks 6th on the list. The all time record is 31.0C... 🧵2/4

Who wants to learn this morning?!

Let's talk about the marine layer...what it is, what it has to do with @KarlTheFog, and why it can create headaches in forecasting heat along the coast.

🧵
#MarineLayer #CAwx We're all familiar with the clouds and fog that we can get in the mornings, but what happens in the afternoons when the clouds go away? Is the marine layer still there? Many times during the summer, the answer is yes!

Time for a 🧵

A hazy view from the nest cam in the City this morning as a temperature inversion continues to trap pollutants near the surface. Now is a good a time as any to do a deep-dive into the science behind these set ups. #CaWx It is important to highlight that when we talk about pollution we are often referring to two key particulates: PM and Ozone. Both tend to be emitted 🏭 from a wide arrange of emission sources and spread outward into the lower levels of the atmosphere.