4/06/06 FCST: KS/NE/IA/MO/OK/AR/TX

[Todd Rasmuson]

this has to be watched extreemly closely... looking at surface data, ie dp's,exc i do believe
we could have a few supercells, with isol tornadoes form w of i-35 just afternoon, between
highway 81 & i-35... dryline is much slower then i thought some of us thought, not to take
away from a likely tornado outbreak later today in the eastern areas but i think non the less
this situation now has to be watched for poss supercells, isol tornadoes

 

[Kevin Polston]

Todd,

My impression is that west of I-35 in OK is not likely. I think it will be more likely east of I-35 later this afternoon and then watch out for eastern OK tonight. So far nothing showing signs on vis satellite in western OK.

 

[David Drummond]

Just a reminder everyone....

(4) Chase Forecasts forum. In the Chase Forecasts forum, we allow two types of messages, as follows.
* FCST is for discussing forecast aspects of severe weather that has not occurred yet
* NOW is for discussing forecast aspects of severe weather that is occurring right now.

Once your out on the road and your chase is in progress, this needs to go in a NOW thread. A few of those have popped up here in the forecast thread already. Posts looking for someone to chase with or just general discussion about where you are heading out to need to go in the DISC thread. I know everyone is excited about such a potential huge day, but lets keep things organized.

This is a very dangerous day ahead, those out in the field need to exercise more caution than usual today and keep your head on a swivel. Things will happen fast and probably violent. I would hate to see anyone become a participant rather than a spectator today.

 

[HAltschule]

I agree with Jim Bishop as there could be some serious Long Lived Tornadoes (several) this afternoon and evening. Current radar shows convective junk just east of Wichita, KS. The dryline/Cold front is evident on satellite in Western Kansas and has TCU building along it. There's still plenty of insolation going on and time for these storms to fire in these areas. Moisture return with DP's in the low 60's is streaming northward and the best instability and dynamics appears to be over South Central Kansas right now. So, I would probably set up shop in Emporia, KS where there is good highway access to go Southwest, Northeast and even to the Interstate depending on where storm initiation actually gets going. But this general vicinity looks primed for some action later today as initiation occurs further to the west this afternoon. By the time it gets to Central and Eastern Kansas, enough heating will have occurred to support some monster sups.

 

[Mike Peregrine]

MD 438 issued for all of central Kansas and Nebraska up and down the dryline: http://www.spc.noaa.gov/products/md/md0438.html

Radar continues to show a few elevated storms popping up near EMP. Vis sat showing pronounced clearing all up and down the dryline ... you can see for miles, all the way through Kansas at this point. Cu has started to develop as well and should provoke a tor watch by 18z ... so looks like we still have some time to play with ... that rocks for those of us at work.

Looks like we're close to moving this to a NOW discussion? - I never know just when to start those things. lol

 

[David Drummond]

Looks like we're close to moving this to a NOW discussion? - I never know just when to start those things. lol
[/b]

Actually, your probably right, won't be long now. I see a second MD now going down in to TX as well.

Shouldn't be any mystery as to when to start the NOW thread....

(4) Chase Forecasts forum. In the Chase Forecasts forum, we allow two types of messages, as follows.
* FCST is for discussing forecast aspects of severe weather that has not occurred yet
* NOW is for discussing forecast aspects of severe weather that is occurring right now. [/b]

 

[HAltschule]

After looking at some more analysis and the well defined cumulus popping along the dryline in Western Kansas, the storms look like they might fire further west than I originally thought. As such, it might be best to relocate between Hays and Salina, KS to be positioned near the interstate for quick access to the best storms. Emporia right now is too close to the convective junk. I'd prob. head further west into the deep instability and follow it eastward once it develops.

 

[Todd Rasmuson]

new mcd out... spc monitoring nc through central ok for possible tornado watch
dryline has def slowed.. i expect supercells to form along i-44 and just e within
the hour...

 

[Mike Peregrine]

Even though the dryline is smack in the middle of KS/NE, the best convergence still remains east of there by about 50 mi. or so. Junction City to Topeka is juicing up nicely now. As well as Concordia. Some convergence is just beginning to show up in Nebraska, but personally I would sit tight in a line from Concordia to Junction City and let these things start rolling my direction if I were out that way. Northeast Kansas will still get its shot, but it's going to light up later on.

We could stand more in the way of Theta-e and quality deep moisture as well ... this will take a little time this afternoon to really develop. MNK is reporting 79/58 ... Junction City 75/61. Not hard to see where moisture is already starting to stack. LCLs and LFCs in the forecast target also have a ways to fall before we are ready for surface-based convection. I agree with the SPC's timing on this so far ...

Can also see some pressure falls beginning to show up. I'm calling NE Kansas by 4:00-5:00 p.m. at this point. By then, this thing is going to be deep and juicy and the storms will get with it.

 

[Bill Tabor]

Interesting how the system has backed up so much from even last night's run. I was expecting MO/AR/IA/ with parts of eastern KS & eastern NE but now seems all the emphasis has all gone north and west into KS. This of course has put me out of the chase up there because I wasn't expecting it to do that and now I am out of place with no time to do the trip. I still wonder about ne TX even though I know the winds will be veered at lower levels. I'm still taking my sweet time on looking at models today - (about to analyze in depth), but I did want to pass on a few things that I jumped to and checked which seem to throw some potential problems into today's KS / northern area chase hype. I'm not saying yet it doesn't warrant a High risk, or that the outbreak won't happen but it is interesting that a few indices and parameters are down on the northern area for both the RUC and NAM. Check out the following:

0z NAM EHI (indicates that 3.37 is the high just ne of DFW whereas there is a secondary max of 2.76 along the KS / MO border). Ok that is fairly reasonable there given the dynamics, but all the other areas around that are between 1 & 2. Heavy emphasis on southern area.
Storm Machine 0Z - EHI: You may have to enter the parameters to get it to display

Jon Davies Experimental Sig Supercell Tornado Mask. I like this one typically as it appears more conservative and less garbage than other similar masks. I believe it includes Cinh due to 700mb capping as standard feature to not draw everything. For both RUC and NAM this Mask prefers the southern area of eastern OK/AR/ and ne TX with only a bit up north.

RUC Based:
21z
0z

NAM Based:
21z
0z

Do you think these things are lying?

Also interesting is last nights run of the 4.5 km NMM WRF Precipitation Graphics. Check today out for modeled radar echoes. This one does show KS as good, but also likes supercells in TX:
0Z Simulated Radar

Had I known a more central KS event earlier I would be up there. Will be looking to the southern area and hoping Jon Davies mask is right. SPC seems to cut off svr in TX I assume because of Cinh but the WRF precip graphics don't seem to agree. I think the biggest problem I may have down on this end is veered low level winds. We'll see how it goes. Good luck to those of you up north. Dynamics may provide you with a bountiful chase.

 

[Bill Tabor]

Ok, I've finished looking at RUC and NAM output along with other stuff (primarily for the Tx area). It's not looking great, but there is some chance of a supercell (outside chance tornado) perhaps in north Tx by 0zish. I like the PRX area near the Red or perhaps slightly east or west of there. NAM has a more favorable outlook with sfc to 850mb winds not as veered. I do note that NAM also shows some upper level divergence over that part of north Tx and eastern OK at 500mb and 300mb. In Tx we do have substantial Cinh right now although breaking near the dryline for the time being as cu is forming (see SPC MSD). I expect a cell to form north of ACT after 21z with large hail as main threat. I may mosey out if I see something interesting. Man, I'm gonna be jealous of all you folks that live north today. Right in your backyard! I still think eastern OK and AR have chance for a big shot, but I didn't analyze that much.