2018-06-24 Event: OK/KS/TX/CO

[Ben Holcomb]

The NAM and GFS still differ a bit on their solutions, but both models depict a deepening surface low in the vicinity of Campo, CO near 00Z/25 on Sunday evening along with a seasonably strong shortwave atop a boundary that seems to be hanging out in the Oklahoma panhandle and SW Kansas. Some extreme parameters along and just north of the boundary. Will they be realized? It's hard to say. 700mb temps are a bit of a concern, as is the surface temps to the south of the boundary.

With that said, the hodographs and general setup with shear vectors seems to be the best that the southern plains has seen in 2018 and I definitely will be out, targeting around Liberal. A nice late season surprise, that's for sure.

 

[chrisbray]

I'm having trouble depicting how real this threat is between all the models. Euro seems underwhelming especially on the moisture side, but I'm aware it underdoes moisture to a degree. Regardless, the capping/ 700 temps seem to be a real concern (along with the mixing), but the models go nuts with the parameters after 0z. I wonder if storms would even be surface based much longer at that point.

 

[Adam Lucio]

Bowdle or Bust on a setup like this. I try not to let the NAMs insanity parameters lure me out for a sunburn this late in the year, but its hard to ignore a deepening low like that with good shear and theoretical juice in place. The way the DL/TP comes together is something you see more typically in April or May in that region.

If you get deep moisture and easterly surface flow north of that low in the high plains though, it could be game on, and thats where I would want to play. Otherwise I would anticipate big time hailers north of the warm front before a major MCS develops.

 

[Drew Terril]

As of the 06Z run this morning, GFS and NAM still differ a bit in placement of the surface low. GFS wants to place a tighter low somewhere near DDC, NAM places it a bit further south and west and a bit broader of a low. Both seem to indicate the WF will be the better play, but both also indicate some early convection plowing into the area and throwing everything off. That said, along and immediately south of the WF, the T/Td spreads aren't too far apart, and shear vectors are good. Usually I'd want to play closer to the TP, but in this case I think I'm going to focus more on the warm front in the absence of boundaries from early morning convection. Based on lack of agreement on WF placement between models, my gut feeling is that it will set up somewhere between the KS/OK border and the US-54 corridor.

Much like with Saturday, I'm off work and it's close enough that I can still be back at work for Monday, so I'll be out.

 

[John Farley]

With the evening runs, the GFS and NAM are really disagreeing on placement, with the GFS continuing to be quite a bit farther north with the surface low and warm front. NAM never really gets the warm front significantly north of the KS/OK state line during daylight, with the GFS having it well up into KS by mid-day. Perhaps some of the disagreement is based on the location of the daytime MCS both seem to be forecasting in KS, with the NAM having it farther east and thus perhaps more of an influence to the west of outflow holding the warm front from moving north. Looks to me like with either model there is a play somewhere near the NE corner of the TX Panhandle, but with the NAM it is more of a warm front or triple point play whereas with the GFS it would be more of a dryline play. But the GFS suggests a warm front play farther north, while the NAM says don't venture much north of the Panhandles. At least that is how it looks to me. Perhaps as it gets closer to the event, the model disagreement will decrease. But regardless of placement, it does look like a good setup with a lot of instability perhaps combined with stronger wind shear than we have seen most of this season. I plan to be out there, but how far north or south looks like a big question right now.

 

[Tim Supinie]

This is less than ideal for a panhandles/SE CO/SW KS chase today. The outflow boundary from morning convection is still surging through the Texas panhandle. The eastern part of the boundary is still actively developing convection, so the east part will probably keep moving as long as that's true. There's a pretty decent temperature differential across the western part, and the clouds are preventing the outflow from modifying. So that will continue to push southward as a density current until we can get some modification of the outflow.



Long story short: this chase is probably toast, save maybe southeastern CO. Maybe.

 

[Dan Robinson]

Agreed with Tim - this day is hosed. Outflow is going to push all the way to I-20 at this rate. As with several other events this season, the CAMs are not initializing showing the morning convection, so they are 100% useless at the moment.

 

[JamesCaruso]

Agree overall today doesn’t hold the promise that it previously did, but if I was out there I would still take a chance on SE CO. Even IF the OFB were to stall and the air north of it modifies - and the modeled extreme CAPE verifies - I would probably choose SE CO for the better mid/upper dynamics, less capping concerns and lower LCLs. Main problem there is models show surface winds developing too much of a northerly component but hey it’s just a model; surface obs look decent at the moment and hopefully the surface winds can maintain enough of an easterly component.