April 13 Severe Threat - TX, OK, LA, ARK, KS, MO, IA

[Stebo]

4 minutes ago, David Reimer said:

Chasing fast-moving tornadoes in mountains and tall trees? Heh. I can think of better ways to spend my day, and I live less than three hours from the I-49 tornado's location. 

 

The northern end of the risk certainly busted that small 10% they had, but the hail/wind verified to at least some extent. The southern end? Eh, we'll see what the report map looks like once any surveys are complete. There were certainly more than two tornadoes and at least one of them was capable of producing EF2+ damage. The watch itself verified probability wise. As for the outlook's probabilities - we still have to get through the night. 
 

 

Based upon the warnings and some of the wind reports, I bet we end up with 15-20 tors.

[David Reimer]

Just now, Stebo said:

Based upon the warnings and some of the wind reports, I bet we end up with 15-20 tors.

Assuming most occurred in the higher tornado probabilities that will certainly verify the level four risk SPC had out for today. 

[Stebo]

Just now, David Reimer said:

Assuming most occurred in the higher tornado probabilities that will certainly verify the level four risk SPC had out for today. 

Yeah most were in or very close to the risk area, there was a secondary cluster a bit to SE in LA, but overall they were near or within the risk area.

[yoda]

New tornado watch out until 6am CDT for extreme southern Illinois, eastern Arkansas, western Kentucky, northeast Louisiana, western Tennessee and western into northwestern Mississippi

60/20 tor probs

http://www.spc.noaa.gov/products/watch/ww0046.html

[Chicago Storm]

1 hour ago, Stebo said:

Since some were quick to bash SPC, I'd like to know which part of this didn't verify

Probability of 2 or more tornadoes	High (>95%)
Probability of 1 or more strong (F2-F5) tornadoes	High (80%)

Because part 1 did easily, and based upon some of the damage pictures part 2 may have with either the tornado northeast of Fort Smith or the one that ran northeast out of Texarkana area. Just because we didn't have a massive tornado outbreak doesn't mean that the probabilities weren't met on almost everything in the forecast. I do expect the 15% to be validated when the rest of the reports come in.

The watch did likely work out in the end, but unless something radically changes...that 15% tor risk busted hard.

[David Reimer]

3 minutes ago, Chicago Storm said:

The watch did likely work out in the end, but unless something radically changes...that 15% tor risk busted hard.

Mmmm we'll see what the report/probability map looks like after damage surveys are complete. 

[Chicago Storm]

1 minute ago, David Reimer said:

Mmmm we'll see what the report/probability map looks like after damage surveys are complete. 

We shall.

Honestly, the QLCS has been underwhelming thus far...which is where I thought most of the tors would come from. Instead looks like little to none from it, and most of the tors were from the early discrete activity.

[David Reimer]

2 minutes ago, Chicago Storm said:

We shall.

Honestly, the QLCS has been underwhelming thus far...which is where I thought most of the tors would come from. Instead looks like little to none from it, and most of the tors were from the early discrete activity.

Agreed. The QLCS in East Texas has been more impressive. 

[weatherextreme]

I don't know what to think about this one ,lol

 

 

 

[SluggerWx]

Here's one from today I haven't seen posted yet. 
 

 

[SluggerWx]

Warning - loud video. Feel for these folks here. The hills in AR have to make some of these wedge/cone shaped tornadoes look like dark clouds until they're right on you.
 

 

[Stebo]

1 hour ago, Chicago Storm said:

The watch did likely work out in the end, but unless something radically changes...that 15% tor risk busted hard.

How so? You do understand how the probability works right? The only way I would consider it busted, was it was a hair too far east, shift it NW 50 miles and it covers both supercells that produced several tors.

[Chicago Storm]

Just now, Stebo said:

How so? You do understand how the probability works right? The only way I would consider it busted, was it was a hair too far east, shift it NW 50 miles and it covers both supercells that produced several tors.

You obviously don't know how it works if you think it actually worked out.

[Chicago Storm]

Here's something you don't see everyday... Check out the DP spread ahead and behind the front in S. Texas.

Low 70F DP's ahead of the front, and below zero DP's behind it. That's a 70F+ DP spread in <100 miles.

[Stebo]

19 minutes ago, Chicago Storm said:

You obviously don't know how it works if you think it actually worked out.

15% Probability of a tornado within 25 miles of a point, like I said if it was 50 miles NW of where it was it would have been completely covered. So yes I do know how it works out.

[Indystorm]

Correct me if I'm wrong, but I thought for a PDS tornado watch to verify you had to have multiple long track (20 mile or more) strong to violent tornadoes.  Did we achieve this?

[cstrunk]

Looks like the risk ended up verifying for me, personally, in Longview, TX. A tornado reported overnight near Diana, TX. 

[Chinook]

13 hours ago, Chicago Storm said:

The watch did likely work out in the end, but unless something radically changes...that 15% tor risk busted hard.

you mean like this? The storm reports so carefully avoided the 15% tornado region and even the 45% wind risk region. Nevertheless, SPC certainly wasn't crazy for issuing a moderate risk.

[Stebo]

1 hour ago, Chinook said:

you mean like this? The storm reports so carefully avoided the 15% tornado region and even the 45% wind risk region. Nevertheless, SPC certainly wasn't crazy for issuing a moderate risk.

If that tor risk was 50 miles west it would have been covered perfectly, that said the majority was right on the edge. There is no way I would bury SPC in retrospect on anything from yesterday except maybe Iowa, but that was known to be a conditional risk hitched upon moisture return. Storms were there and severe but the low level moisture wasn't quite sufficient for tornadoes.

[WhiteoutWX]

I think a 50 mile westward shift of all risk areas would have made this event verify much better. There were a ton of hail reports on the very western edge of the marginal risk. The dryline was slower to move east than models forecast (per usual), and this likely accounted for this slight misplacement of the risk areas. But overall I'd say the forecast looked pretty good to me by SPC.  

[Chicago Storm]

This was not a 15% tor day. Plain and simple.


.

[MUWX]

1 hour ago, Chicago Storm said:

This was not a 15% tor day. Plain and simple.


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Wasn't a 5% day either 

[Stebo]

5 hours ago, Chicago Storm said:

This was not a 15% tor day. Plain and simple.


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Keep trying to fit that square peg in the round hole. Draw a line from Bronson to Texarkana 40 miles either direction, and you have a verified 15% just a hair NW of what it was. Sorry to break it to you but you are wrong here and statistics back it up.

[Chinook]

EF-2 tornadoes have been surveyed in Bryceland, LA and Macomb, MO

[Quincy]

The overall risk area was fine. I wouldn't nitpick over the 15% tor in the Arkansas vicinity. The general idea was there, as it was on 4/27/14.

As far as tornado probabilities farther north (north of TUL-SGF), the data simply did not support much of a tornado threat in the region. I think the wind fields were more of an issue than low level moisture, but it's a moot point now.

It's not uncommon at all for significant tornado threats 200-300+ miles away from the center of a low, where weaker (but still sufficient forcing) coincides with larger buoyancy and longer residence time of discrete/semi-discrete storm modes.

This could have been a higher-end event, as Andy eluded to, if the upper level system had arrived a little bit later.

[OUGrad05]

The location of the 15% could have been shifted to the west a bit but nature trolled SPC a bit.  It happens.  The 15% was warranted in a limited area and despite the tors trolling to the NW side of the 15% given convection that had occurred and the relatively untouched air where the 15% was, they generally got it right I'd say.

[Jonbo]

Decided to chase in SW Iowa around Corning-Red Oak-Atlantic-Massena area and while it was a bust on classic looking tornadoes, a group I came across let me follow them and gained a lot of valuable knowledge and saw a funnel with a brief touchdown when we were reviewing footage (waiting on NWS review). Surprised me how quickly it went from 50-55 to 80-85 degrees in less than a minute, if that. 

First photo was when the initial tornado warning came out and may have had a brief touchdown also according to some of the radio chatter but we couldn't see it from the distance. Second photo was the major dust kick up; video of someone else getting too close to it below. Third is a screenshot from my video and 4th was taken by group in front of me.

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