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There is increasing confidence that some of the coldest air of the season so far could arrive late next week, along with some snow potential for some areas! Details here: youtube.com/watch?v=YkE2juqP…

There’s a lot of debate around this “tornado”, as NWS Birmingham confirmed no formal tornado damage from this signature, despite a TDS lasting multiple scans and going up a few tilts (debris signature extending a few hundred feet). So, was this a tornado and did the NWS flop? First off, no, the NWS didn’t flop on this survey. Multiple spotters, including the NWS found no damage that would fit within the EF-scale bounds (starts at 65mph for an EF-0), therefore a tornado can’t properly be identified. What about an EF-U? With no visual confirmation of a tornado or any real indicators of a start-end point, it’s very challenging to confirm if it was a tornado at all. In Fall, tree’s leaves begin to weaken and fall off. Usually from October to early December (varies by region), there are a ton of loose leaves around, which can be easily picked up and lofted. Now, many meteorologists & enthusiasts don’t know exactly what lofts these leaves and perhaps tiny twigs so far up to be detectable by radar. Most likely, it’s a very weak surface vortex, like a gustnado, that is nowhere near strong enough to do damage, but is strong enough to loft thousands of leaves and be detectable through radar. Likely somewhere within the 40-60mph range. While it’s hard to officially classify these signatures and likely weak ground vortex, or even just a strong straight-line surface gust, These may still not be completely harmless 100% of the time. Without proper visual confirmation of a tornado (or no tornado), radar has a hard time discerning between what is just a weak, likely non-tornadic vortex or straight-line gust lofting leaves, and what might actually be a damaging tornado. There are definitely clues, such as TDS size, depth, TVS/VROT strength, etc. However, our job is to help notify the public of a potential hazard, and encourage safety from said hazard. We’ll continue to mention these signatures as possible tornadoes, in the event that a tornado is actually ongoing, and it’s not just a deceptive leaf whirl. We’ll be looking into ways to better communicate these events in real-time. This is a lot of text, but I hope that this provides some insight and gives some perspective on the tricky nature of these non-tornadic TDSs (Tornado Debris Signatures).

Euro 2 weeks ago vs forecast now for the same time

Damaging winds and a few tornadoes remain very possible across parts of Texas, Oklahoma & Kansas tomorrow. The storm mode will likely be quite messy, with a mix of line segments, and transient supercells. However, any organized or mature storms that develop and are maintained will have the greatest chance to produce severe hazards. There is a conditional risk for significant (EF2+) tornadoes, mainly based on storm mode and instability. Recent runs of the CAMs have trended upwards in terms of instability, which could indicate a higher severe threat, but again, an unfavorable storm mode could thwart a more organized/significant severe event.