04/21/05 FCST: Central/Southern Plains

[Mike Johnston]

Yes, Jeff - latest runs also have the surface low further south - now moving across central KS mid-afternoon rather than central NE - and an area of convective inhibition and higher LFC over SW MO, which earlier had looked most promising for Thursday evening. At the moment, I kind of like Coffeyville - longitude seems to correspond well to advancing system/diurnal cycle, and it also happens to be mid-afternoon bullseye for deep layer shear at 48 kt, and well within workable LFC height below 1,500m. We will likely still start in Olathe, with a good chance of heading south depending on the morning outlook. Hopefully, overnight and early am storms will be confined to northern tier of KS so surface environment further south will not be too stabilized.

 

[Justin Walker]

Wow...going out on a limb, a high risk. As Jeff mentioned, we have struggled with the stratus the past couple of days. However for tomorrow, as my friend Adam pointed out, I see some mid level ridging further upstream that will really help mix out the stratus that we have been dealing with along the dryline. With that being said, I agree with Jeff about Eastern OK area for tomorrow, helicity will be strong in this area. After a restless night of sleep for us all, we'll see in the morning.

 

[Jeff Snyder]

Before we all get too pumped about tomorrow, it's important to realize that the GFS is splitting out a considerably different solution than the NAM, with a very weak, elongated surface low/trough from southeatern NE to northeastern OK, with southwesterly flow across all of eastern OK, KS, and surrounding areas... Additionally, it forecasts the stronger mid-upper level flow to stay west of the warm/moist sector tomorrow afternoon... I'll just say that if the GFS looks to verify, I'm going to stay home...

That said, go NAM!

I'm still saying SLT risk on 6z, mainly because I think we need to wait until morning to see what the various boundaries are going to do to tomorrow's potential. Heck, there's still an awesome OFB cruising southward across western north Texas associated with the southern OK convection... I really would like this OFB to stop making southward progression, since it could hose tomorrow if eastern OK stays in cooler, drier outflow air. That said, if it can make it's way northward tomorrow afternoon to near I40 corridor, I'd be VERY pleased.

EDIT: Err... I meant MDT... I'm forecasting 15% tornado prob eastern KS/western MO; 45% hatched hail in MDT risk area from eastern KS/OK to northwestern AR and most of MO... Just a hunch... :wink:

Regardless, I think we may end up with enhanced tornado potential farther south associated with an OFB that may set up somewhere in the area... Then again, the same OFB may squash tornadic potential... We shall see...

 

[Mike Johnston]

Thanks for the update, Forecaster Carbin LOL. At any rate, encouraged that my Olathe to Coffeyville axis still holding up. On the other hand, I could just stay on the back deck here in Lee's Summit and perhaps do just as well. It's the deep layer shear that will distinguish Thursday, I believe, from what we have seen so far this week.

 

[Anthony Silver]

It's official, tomorrow will be a chase day. Just read the latest SPC outlook. MDT risk for SE Neb, E Cntrl KS, SE KS and W MO. Tornado Outlook is 15% and Hail is 45%. According to the outlook, supercells will be possible, with a widespread severe weather event expected.

 

[Jim Bishop]

EDIT: Err... I meant MDT... I'm forecasting 15% tornado prob eastern KS/western MO; 45% hatched hail in MDT risk area from eastern KS/OK to northwestern AR and most of MO... Just a hunch... :wink:

Regardless, I think we may end up with enhanced tornado potential farther south associated with an OFB that may set up somewhere in the area... Then again, the same OFB may squash tornadic potential... We shall see...

I agree. I believe the best tornado potential to be in south central/southesat kansas, even into Oklahoma. Like Jeff said, wherever outflow boundaries may be by late Thursday afternoon/evening should be the area with the greatest tornado potential. I'm actualy quite surprised the SPC did not mention anything of that sort. But regardless, forecast hodographs in the areas I just mentioned look good for tornadoes.

If I could chase I'd be in southcentral/southeast Kansas....

 

[Mikel Shively]

My latest storm outlook can be found on my website. I really like what I am seeing. Looks like thunderstorms will clear out early enough that we will get some good heating/instibility. Starting to get a little excited now

 

[Eric B'Hymer]

Spc has a PDS public statement out now talking severe weather outbreak for eastern ks, w mo.

 

[Shane Adams]

Everything I like to see is finally pointing to one general area, in NE OK/SE KS. I'm not worrie about the proged SSW surface winds, as I think local enviroments will easily take care of that in and around any boundaries or storms. I'm leaning more towards the KS/OK border area, as the 850 winds are a bit more southerly in this area as oposed to further north, which will enhance the shear. Instability looks to be possibly the best we've seen so far in the S Plains, as CAPE values in excess of 3000j/kg are being generously forecast. Main thing that jumps at me this morning is the surface low/mesolow thingy in S Kansas. This could possible create a buldge in the DL and I want to be east of that. So that makes my target Bartlesville to Independence for a starting point. Could very likely move north to Chanute to better position ourselves out ahead of the DL buldge.

I've got a hunch SPC will eliminate the 15% tor area, at least the northern half if not all. Wouldn't be a bit surprised to see the tor bullseye shifted south a bit to NE OK. Now I will go see how right or wrong this hunch is, LOL.

 

[Marcus Opitz]

Well... my target area is going to be the I-71 corridor from Kansas city to Joplin, That area looks to be the best comprimise for terrain, and lack or clouds at this time.

I wont get off work until 7pm so I hope I dont miss any action. I personally think at around 5-7pm things will get going. If i initiation occurs sooner, 13 hwy to springfield would be a better choice, but I dare not go any farther east, as the hills are not conducive for chasing.

Anybody care to guestimate storm initiation time??? Curious what you all think.

Good luck all.

 

[JHadorn]

Most of the discussion for my area is that 2:00 PM is when it's supposed to start cooking. Looks like I'll be possibly making a trip to Falls City today.

 

[Philip Flory]

New RUC run seems in good agreement with a target near the Independence to Chanute area. New RUC run indicates conv initiation nearer the SFC low close to 18-20z.. with farther development southward/more isolated accross SE KS/NE OK. It is nice to actually have some decent mid-level flow to work with, especially on the order of 40-50kts. Appears low-level shear may be a bit weak for intense tornadoes/however strong directional profiles should be supportive of long-track supercells with isolated tornadoes. Strong heating coupled with 65 td's would appear to be supportive of 2500-3500 J/KG SBCAPE values by 21z... latest RUC run picks up on that very well with a bullseye over NE OK/SE KS/SW MO.

Plans are to sit in ICT until around noon and refine target area.

 

[Billy Griffin]

GeeeMoooNety... I hope I am wrong, wish I were, again, hope I am. OU Mesonet already shows most of western Oklahoma's winds now veering from the SW and the cold front appears to already be past or right on top of Woodward (points northeast ~ southwest of there).

I was sure hoping this thing would slow down so we could get some initiation near Central OK (where I am currently at).

Even here in Norman, winds are starting to come more out of the southwest now. DPs are still okay, but the winds... ughh.

I was planning a 2:30pm departure from the campus today after teaching my last class and hoping for initiation close by, but unless this thing slows down, heck, it'll be in Arkansas by 3pm !!!

First day with abundant low-level moisture, all-day surface heating... figures! :evil:

Again, I hope I am wrong. But I guess for all the chasers up near Springfield, MO - good luck !!!

 

[Jeff Snyder]

GeeeMoooNety... I hope I am wrong, wish I were, again, hope I am. OU Mesonet already shows most of western Oklahoma's winds now veering from the SW and the cold front appears to already be past or right on top of Woodward (points northeast ~ southwest of there).

I was sure hoping this thing would slow down so we could get some initiation near Central OK (where I am currently at).

Even here in Norman, winds are starting to come more out of the southwest now. DPs are still okay, but the winds... ughh.

I was planning a 2:30pm departure from the campus today after teaching my last class and hoping for initiation close by, but unless this thing slows down, heck, it'll be in Arkansas by 3pm !!!

First day with abundant low-level moisture, all-day surface heating... figures! :evil:

Again, I hope I am wrong. But I guess for all the chasers up near Springfield, MO - good luck !!!

Billy,

We share concerns. Winds in along and west of I35 (particularly in northcentral OK) and really veering. Even Ponca City now has SSW winds... I'm getting very concerned that this wind shift is plowing too quickly to the east! Heck, Medford currently has due westerly winds! Strong pressure rises behind this feature tell me that it'll continue working eastward, though the various mesolows last night make me a little suspicious of using pressure tendency charts.. At any rate, I'm not really sure what the feature is, since the airmass behind it still has ~65 degree F Tds, so that rules out the dryline; I think it's a pre-frontal /pre-dryline windshift of sorts.. Regradless, this better slow down else we'll end up with 0 srhelicity today...

 

[Mike Johnston]

The most specific official prognosis re: initiation I have seen is from the ICT HWO:

SEVERE THUNDERSTORMS ARE EXPECTED TO RAPIDLY DEVELOP BETWEEN 1 PM AND 3 PM. THE ESTIMATED LOCATION FOR INITIATION IS ROUGHLY NEAR A LINE FROM COTTONWOOD FALLS TO ELDORADO TO ARKANSAS CITY.

Typically, choice of target today between triple point area and SE quadrant of surface low. In reviewing the principle obstacles/concerns:

1. Cloud cover/surface stabilization in wake of last night's convection isn't looking like much of a problem, as storms stayed N of KC area and are now pushing NE towards Iowa at 35mph, and it looks like we will get sufficient clearing from W to E over much of KS and OK.

2. Verification of forecast eastward progression of 500mb winds also looks good, RUC has 40-50 kt field reaching the KS/MO state line by 00z.

3. Would like to see forecast helicity lined up a little better; NAM showing highest values over SW MO, but this is also area of a bit higher LFC's w/ greater chance storms may have lined out by the time they reach this far east.