2017-03-06 EVENT AR/KS/MO/OK

[Brian McKibben]

SPC day 2 enhanced risk for the Ozarks.

Surface:

12z NAM and 4km NAM on 20170305 vs 20170304 puts the DL further west by about 80-100 miles. It shows the DL stalling somewhere near the I-35 corridor with a triple point setting up in NC Okla.

New 18z 3km NAM Td map:


Low 60 Tds seem reasonable given current conditions via mesonet.



I don't think we will see any Tds > 65 due to the lack of abundant rich (>70) low level moisture per 12z 20170305 soundings along the gulf. South TX is currently showing low to mid 60 Tds.



Even though Tds are in the low 60s, I do not think moisture will be much of a problem this early in the season. Also, there has been decent moisture advection the 2 days prior to event. The depth of the moisture from CRP is > 1km.

UPPER:

As noted in SPC discussion, most upper forcing will be well to the north of the target area. This is seen on 18z NAM with a negatively tilted trough at 500 hPa.



If i remember my streak streak quadrants correctly this put the Left Exit region in IA and MN. But we could also seem some PVA in the right entrance region (correct?) which would be in the KS and OK/TX panhandle area. 75 LRs of -7° C per km seem decent but not amazing.

At 850 hPa we have 45+ kts of SW flow east of the DL by 00z. This cmobined with slight backing of surface winds after 00z increases 0-1km helicity to AOA 200 m2/s2.



CONCLUSION:

With all that said, tomorrow could be a day that gives us at least a few chasable storms. NAM puts some storms in the enhanced risk region ahead of the DL in the warm sector. But I am a guy that loves that "Dryline Magic".

I'd target the TP if it was me, because the terrain in the enhanced risk area is not fun. Good luck to all.

Here is a bonus sounding. Somehow I found the PDS Tornado Just east of OKC metro near Shawnee.

 

[Ethan Schisler]

Mods....lets add Iowa to this thread shall we? The latest 18z NAM has mid to upper 50s dew points being pulled northward into South Central Iowa tomorrow afternoon/evening ahead of a cold frontal boundary. Even though this is a cold front, many models are still showing ESRH values of 200-300m2/s2 ahead of the front....this underneath ML CAPE values around ~1000 J/KG by 00z. Storm mode is going to probably be a bit messy, however if we can get any semi-discrete supercells or breaks in the line in this area, it could definitely foster an isolated tornado threat in my opinion.

Moisture is going to be the biggest question in my mind this far north, as we will need mid to upper 50s dew points to attain an environment similar to the sounding below....although as OP mentioned, this may not be an issue given the low to mid 60s dew points being advected northward off the Gulf of Mexico currently.

While certainly not the ideal setup, its only March 6th, and would be a mere 3 hour drive west for me, so I'll keep tabs on it and see how things look come day-break tomorrow.

 

[Royce Sheibal]

NAM 4km and HRRR are really putting on a show this morning. Those STP's and SCP's are looking unusually high for this time of year. Not only will we need to add IA, but also MN i think. We've got a nice pocket of theta-E advection pushing into SW MN this afternoon. I'm liking the MN/IA area to go early between 3-4pm and then KS and MO to start rocking out around 5 or 6. I was hoping the front would slow down so Omaha could get some action, but NAM 4km only gives us a slight chance at pops before the front pushes through around 3pm, so bummer. Good luck today boys! Things could get really wacky out there.

 

[Brian McKibben]

14z and 15z HRRR are pretty aggressive with a lone long-track supercell in SE Kansas this afternoon. A quick look at the sounding for that region is pretty impressive.

Also of note, the 12z and 15z RAP show precip along the DL from Wichita to OKC this afternoon. We are starting to see some breaks in the could via 1km vis and OK Mesonet.



New target for me would be I-35 along KS/OK border and then adjust based on current conditions around 2 pm.

 

[Steve Holmes]

SPC: Tornado watch likely soon (95% probability at 2:50pm) for much of SW MO, SE KS, NE OK & NW AR. Three watches already out from central MN to W MO. Clouds dominate the W half of the Enhanced area. Not a lot of breaks according to the 2015Z satellite picture. Has lightened up in Joplin in the past hour. Was heavy overcast. Now hazy sunshine. You guys know more about this than I do, but how much of a damper is the cloud cover likely to put on this situation?