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The radar returns on that convective complex are starting to wane. It's possible this lays out a boundary that backs the surface winds and enhances the critical angle on the hodographs. It's more of a low probability and speculative scenario, but the 14Z HRRR does kind of hint at that. Instability would still have to materialize of course. If it happens just right the MO/IA/IL border area might still be a prime spot.

It may not be as focused or as certain as it appeared last night, but odds still favor a significant outbreak including tornadoes. The SPC is still pushing EF2+ tornadoes today afterall.

3Z SREF suggests only modest tornado potential in western/northern IL. Verbatim the higher tornado probabilities are in AR/MO/TN/KY/IL border area. If I were to go off only the latest HRRR and SREF runs I think I'd be considering a downgrade right now. But...it's a big low with an impressive kinematic environment so maybe they'll decide to keep the 15% sig-tor area on the 13Z update and wait and see what the morning convection does before making big adjustments. I will say that the 10Z HRRR still has a pretty good parameter space in IL just on a more localized scale now.

I don't know about the high risk. HRRR looks potent now, but what will things look like tomorrow? We've seen this type of over-reaction by CAMs only to curtail their outputs a few runs later or the day-of ends up being a bust. Nah...I see < 50% of a high risk tomorrow. I'll accept a good ribbing if I'm wrong though. We'll see.

^^^ 3km CAPE of 237, LCL of 372, and 1km SRH of 274. Yikes.

Those UH tracks on the 0Z HRRR are gnarly. They're also expanding at a rate of 65 mph.

Man...I'm getting up to 70 mph right movers on some of these soundings.

15Z RAP is primed with a convective melee of activity in the warm sector there in IL.

Another day and another sharp decline. The NSIDC did call the top as March 5th.

March 5 with a 5d average of 15.047 on NSIDC might be the max. I'd give greater than 50% odds at this point. We'll see.

RSS was up in February, but not as much. ERA was only up by 0.02C. I keep wondering if UAH is contaminated by what happens in the stratosphere more so than RSS. If so that would partly explain UAH's 0.13C/decade trend which is far lower than what any other dataset shows.

Zharkova 2019 was formally retracted by Nature. https://arstechnica.com/science/2020/03/paper-that-claimed-the-sun-caused-global-warming-gets-retracted/

Maybe. I was watching aerosol optical depths closely after that eruption and while there was a lot tephra lofted into the troposphere it didn't appear as if much sulphate aerosols made it into the stratosphere. I think the Australia wildfire smoke is a better hypothesis at this point. In regards to the troposphere...volcanoes typically cool this layer. I don't know of a case where warming resulted from an eruption. And I'm not understanding the link with smoke either. I thought smoke was more effective at blocking incoming shortwave radiation than it was at trapping outgoing longwave radiation.

Hmm...Dr. Spencer is suggesting the smoke warmed both the troposphere and stratosphere. Typically aerosols cool the troposhere and warm the stratosphere. This is an unusual event in that the spike up is observed in both layers. I'm a bit skeptical of his smoke causing radiation induced warming (aka greenhouse effect) claim, but I'm open to hearing what evidence he presents. The thing is that the February troposphere anomaly is primarily the result of warming in the NH. My first thought is that the record +AO may be partly to blame with the spike.

I was not expecting that. The average ONI over the last 3 and 6 months is only 0.5 and 0.3 respectively. Somewhat interesting...the UAH stratosphere temperature spiked up this month. This is only the 3rd time a spike has occurred. The other two were from El Chichon and Pinatubo.