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Severe WX Severe Weather Threat 3/14-3/16

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Not that CSU ML guidance should have too much weight at this range, but the fact severe probs are the highest they've ever been for this event reflects the marked uptrend over the last 24 hours. The southern bias tornado signal probably following best instability but an EF3+ tornado threat will certainly extend all the way into E MO and C IL.
 
Some people in this thread really need to read more and post less.
Yea guys, especially once the event gets going, can we try to keep it to posts pertaining to tracking the event itself? It's been very hard to keep up with most good info when you refresh and there's a whole new page to read. A lot of which is the same thoughts over and over again. And the event hasn't even started yet. It's going to get insane in here. Obviously I'm not an admin, but just my 2 cents.
 
Looking at the SPC mesoanalysis charts, it does appear that the NSSL models and the NAM 3k are slightly overdoing the moisture return for today's event at least through 16z. The moisture is a little further south than modeled and there is slightly worse coverage of 60s dewpoints at the moment. Also, it's not a CAM, but the RAP seems to have the best handle on the moisture followed by the HRRR.
 
Why does Middle TN seem to be getting smoked when the thermodynamics don't come close to the weather further south? Is this possibly just a model bias?
This would actually make sense if this is indeed an analog to 4-27-11. The secondary low is displaced further north than in 2011. The low was over Iowa at 980mb. This one is stronger and further north by a couple hundred miles. It would only be logical to assume if you got the same type of event around the same locations, move the points northward by those couple hundred miles…Hence TN getting wrecked
 
The Cape values are actually a bit higher than 2000j/kg.

Most of the OWS has SB-cape exceeding 3000j/kg, which for mid march is absolutely ludicrous.
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I agree, but he raises a valid point. If we're talking potential limitations for Alabama it would be atmospheric recovery and instability. The timing, as well as how long cloud cover remains, is going to influence the ceiling for some areas.

There's absolutely sufficient CAPE for a significant outbreak, however, if we saw the coverage and intensity of CAPE values increase to the east and west it would, IMO, increase the potential for various parts of Alabama.
 
Looking at the SPC mesoanalysis charts, it does appear that the NSSL models and the NAM 3k are slightly overdoing the moisture return for today's event at least through 16z. The moisture is a little further south than modeled and there is slightly worse coverage of 60s dewpoints at the moment. Also, it's not a CAM, but the RAP seems to have the best handle on the moisture followed by the HRRR.
Trey mentioned this
 
After looking at the 12z runs, I really fear there will be a "glancing" blow in central Alabama by morning convection. Stout enough to leave some boundaries, but also fleeing to the north to allow high octane air in behind them. These boundaries could become focal points for upper echelon rotating updraft. It seems like the cams are beginning to key in on that.
 
I agree, but he raises a valid point. If we're talking potential limitations for Alabama it would be atmospheric recovery and instability. The timing, as well as how long cloud cover remains, is going to influence the ceiling for some areas.

There's absolutely sufficient CAPE for a significant outbreak, however, if we saw the coverage and intensity of CAPE values increase to the east and west it would, IMO, increase the potential for various parts of Alabama.
The failure mode regarding atmospheric recovery has kind off dropped at this point, none of the mesoscale models show restricted WMAA or a reduced instability field.

I think at this time currently, the biggest failure mode for Saturday is a messy storm mode, and when I say “biggest” it’s not that high of a chance, but nonignorable.
 
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