re: Severe weather threat continues today for parts of the southeast - Threat is Over.

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I’m in the 30% zone.

Does that also mean there is a 70% chance there won’t be severe weather?

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Not really, it means there is a good chance of severe storms in that area. A 30% risk is a significant risk.

I get that 30% seems low, but again, it is significant. Even high risk days are usually 45%.

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thought the 30% was something along the lines of reasoning that there is a 30% chance of a severe weather event, thunderstorm or tornado, that will occur within so many miles of any particular location.

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That’s exactly right. It means there is a 30% of severe weather within 25 miles of a given point in that area.

I've been in west central Georgia for a few years now and always follow severe weather events in the area. It seems like without fail, they largely dissipate by the time they reach the Georgia/Alabama border. I know Georgia will occasionally get hit, but it seems like Alabama always gets slammed then it quickly calms down.

Is there some reason for that, or am I just imagining things?

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It is like the OT, but for storms.

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Is there some reason for that, or am I just imagining things?

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It’s probably a combination of different things. I don’t have the meteorological knowledge to really explain it, but I can list a few factors that probably contribute. As storms enter Georgia in these events, the better dynamic support from the low pressure system is likely pulling away many times, so the ingredients for severe storms/tornadoes start to lessen (wind shear, helicity, etc.). A lot of these events occur when it is after dark, so when the storms enter Georgia it has often been dark for several hours so there is less heating from the daytime to coincide with the storms, which can mean less instability for the storms to work with. Another thing that sometimes comes into play is a wedge of cooler air coming down the Appalachians.

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Roll Tide Ravens

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That makes sense, appreciate the answer. We always keep an eye on it, but have been fortunate so far. When the big storms came through on March 19, 2018 one small twister ripped up the GDOT storage shed on I-85 not too far from us, but all of the serious storms were in Alabama.

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Do we have any new terms that the SPC have added this year?

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The only thing they changed were the Advisories. I think they pretty much did away with them, and will use similar guidance in the discussions and outlooks instead of cluttering the warning process with all the different advisories.

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But to answer your question, I'll guess it has something to do with the Appalachian mountains that causes fewer tornadoes. Or possibly that the Gulf of Mexico, which provides a lot of the instability, isn't directly south of most of Georgia.

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It really is weird how localized geography can affect a given storm, or system. Like you said, it can impact negatively and serve to decrease tornado development. Or, it can be the exact opposite. There is pretty good research into this going on right now in the Sand Mountain area of Northeast Alabama. Usually, storms seem to weaken as the move across the state, but often restrengthen when approaching the mountainous terrain. They still don't completely understand why, but they know it has to do with the microclimate that exists in the area.

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I'm no weather expert but it seems like this stretch of Southeastern states has really ramped up in activity to rival or even surpass Tornado alley

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That's why they call it "Dixie Alley", which I'm surprised hasn't been canceled yet. I wouldn't say that it has ramped up, necessarily. The area has always had more than it's fair share of tornadoes. What sets it apart from Tornado Alley is population density. There are so many medium and larger cities and towns that aren't separated by that much real estate. When you have a long track tornado out west, it can go for 20 miles and never cross paths with a town. That's not the case in MS, AL, TN, etc.

I assume those numbers embedded are not good for you if it's a "7"