2011-05-08 FCST: OK/TX/KS

[John Schlenner]

The NAM and GFS both show a 60+ kt 250 hPa jet nosing into the area on Sunday Afternoon/Evening, which could provide the forcing to break the cap and trigger isolated storms along the dryline. If anything forms, the high CAPE environment and decent wind field would allow it to go severe. Not expecting a big event but it's worth watching.

 

[Doug Drace]

Im in total agreement on this day. Hodos/Skew T are impressive, lending high confidence on my part that IF a storm or two can fire, it wont take long for it to go Severe, and potentially Tornadic. This certainly is NOT the Big Day of the week, but its going to potentially be a nice treat for those of us who chose to venture out and give it a chance. LCL's could be lower, but they arent crazy high, and personally I really like this setup. May be a few less chasers out with it being Mothers Day, and with it not being an Outbreak scenario, which is just fine and dandy by me Generally looking to be in the West Central OK/NW OK region on sunday. This 0z Hodo and Skew T are from the I-40 area between Weatherford and El Reno. A little mouth watering.......

 

[Jeff Duda]

That is an interesting sounding, Doug. Surface moisture is great, but the GFS apparently neglected to mix out the PBL. I wonder why the moisture lapse rate is so parallel to that of the temperature, especially with the sounding being valid at 00Z. Either that, or the PBL is very shallow and can only be seen in the lowest 50 mb or so of that sounding (I do see some hints of mixing there). There's no parcel path drawn there, but there's definitely some modest CIN for a surface-based parcel to punch through there. Looks like a lot of surface convergence at the dryline, though, so that may be enough to kick off convection.

 

[Steven Howell]

It sure looks like a beautiful setup, I am hoping for some action maybe on Monday, or Tuesday, my wife has done put the kabosh on Sunday with it being Mothers Day. If I didnt get killed by a tornado that day, I would likely get killed when I got home....

Kind of let down that the models were showing some decent areas along the dryline in NW Texas, SW Oklahoma for Monday, and it looks like its shifted to Tuesday, Wednesday, and I cant gett of work on Wed....the timing sucks this year! Really hoping for something on a weekend soon.

 

[Matt Hunt]

I'm planning on heading to the plains on Sunday, or possibly tomorrow evening to be closer to wherever I end up targeting on Sunday. Too early to call, and models have been all over the place on this one. Instability is certainly not a problem. The cap appears to be an issue, although it seems to me like all models have been overforecasting the cap this year. 4/19 is a perfect example, as even the RUC in the morning showed a strong cap in place all day, and lo and behold storms fired at 19z! I'm more concerned with a lack of good shear, and models have been very spotty on where the best shear will be. Winds certainly are turning with height, but not really increasing with height. LCL's are also a big concern of mine, and the GFS is even forecasting relatively high LCL's all week throughout the area now. Either way, I'm chasing Sun-Tue at least, and possibly Wed, so I'll chase whatever I can get!

 

[Logan Karsten]

It seems there may be a very small window of opportunity spatially and temporally out in central Nebraska tomorrow. Looking at the 12Z NAM, a tongue of 3000+ ML CAPE will be present near the Kearny/Grand Island area. While most of the good low level shear and helicity is mostly further east, there is some overlap that may yield a threat of an isolated tornado out in this area. Especially with the cap eroding by 00Z, according to the 12Z NAM.

 

[Scott Hammel]

I've been keeping an eye on the model runs over the past few days regarding Sunday, in particular the northern play in NEB/SD. There are plenty of ingredients to like so far, no doubt about it. The CAPE will be there and model runs are consistent in showing 60's dews returning all the way up in to SD with the cap eroding in north/central NE right around 0Z. Like Logan mentioned, the helicity values, especially on the 0-1km scale either stay too far E or don't spike in the target area until after 03Z. Unfortunately at that point, the cap starts to fill back in as well. The SFC winds aren't the greatest either but manageable. Ugh, this is a tough call. I don't think the tornado chances are very high, but if the timing could come together just perfectly, something might happen. And isn't that storm chasing for ya? Right now, I'm leaning toward heading out for this to give it a chance and I like an area between Valentine and North Platte or perhaps somewhere along 183 slightly further E. I don't know though, tough call.
Random central NE hodo at 0Z

 

[Doug Drace]

High LCL's in OK/TX tomorrow have me less confident in tornadic potential than yesterday, however there still could be some huge hail with any supercell that can punch through the cap, which could be fun You never know, maybe conditions will change a little for better surface based supercells by showtime tomorrow. Still plan to chase no matter what the models put out between now and then...just a lil more bummed that the tornado probs seem to be heading in the wrong direction. I will be plenty happy to see some gorgous storm structure, considering we still have some better than average tornado probs coming mid-week.

 

[John Schlenner]

The 4km SPC WRF fires off a good amount of discrete convection tomorrow evening...I'm not buying it to that extent but I do still expect a few storms to fire off the dryline tomorrow evening. Steep mid-level lapse rates should allow for some significant hail with anything that can manage to get going...

 

[Derek Weston]

Our play looks to be toward the SE end of the WF in E/C Nebraska. Both RUC and NAM depict a nice little piece of middle level energy to hit the region between 21-0z. This, naturally, coincides with cooler temps aloft and a few cells on each model's simulated reflectivity. Hodographs in the area, while not large, depict appreciable turning with height.

 

[Mike Johnston]

Our play looks to be toward the SE end of the WF in E/C Nebraska. Both RUC and NAM depict a nice little piece of middle level energy to hit the region between 21-0z. This, naturally, coincides with cooler temps aloft and a few cells on each model's simulated reflectivity. Hodographs in the area, while not large, depict appreciable turning with height.

Yeah, agree that is where the setup today looks to be shaping up. I would actually tend a little more to SE Nebraska. Being near Beatrice by 21z might be a decent position w/ N/S road option via U.S. 77 and E/W access via U.S. 136. Advection of high theta-e air to that area is actually pretty impressive and instability looks to really spike by late this afternoon. The best helicity is removed a little to the east, but not by much, so there's a decent possibility for the ingredients coming together.

 

[jshields]

the 14Z run of the HRRR show a large cluster of storms developing to the northwest of omaha around 5-6pm and slowly propagating to the southeast. i'm worried these might be slightly elevated but right at the beginning you might have a shot of a tornado. otherwise given the slow movement, i'd be worried about heavy rain besides the large hail threat.

http://rapidrefresh.noaa.gov/hrrrconus/jsloop.cgi?dsKeys=hrrr:&runTime=2011050814&plotName=cref_t2sfc&fcstInc=60&numFcsts=16&model=hrrr&ptitle=HRRR%20Model%20Fields&maxFcstLen=15&resizePlot=1&domain=t2&wjet=1