09/30/09 FCST: KS/CO/NE

[Darren Addy]

Time to switch off looking at models and look at the real time conditions. This one looks super-iffy but I still wish I could chase it. This could be a swing-for-the-fences-and-strikeout kind of day, but I still respect those taking the big swing.

Given the cap, I think you have to go for the dryline-high temp combo. That means going farther south, where (not coincidentally) you're going to find more moisture. I'm liking Dodge City. Ignoring my first sentence (above) the RUC model skew-t looks the most loaded at 0z for DDC and I'm also liking the helicities in that area.

The cap might actually provide an environment for a storm that can make it to have the area all to itself, which would sure be picturesque - though I may be wishcasting there.

Goodland forecast discussion thinks the best severe chances in it's CWA are at McCook, but I'm doubting great moisture return up there before dark. Could be wrong, though.

 

[Tony Laubach]

Bottom of the 9th, two outs, two strikes, based loaded and down by 3...

He's right, its a swing for the fences type of day... and I think I'm one of many in the batter's box.

I'm initially targetting Goodland for a split-the-difference... potential sits in northeast Colorado for marginally severe storms... potential sits in southern Nebraska... potential sits in western Kansas... there is potential everywhere, but each spot has its drawbacks..

Goodland seems reasonable cause it gives me the option to shoot in any diretion fairly quickly. It puts me closer to the initiation points in the north while allowing me a quicker recovery time to catch a northeast moving storm. I'm a bit far from the southern targets, but they'll me moving more in my direction, so I can close in quicker.

The parameters are awesome in most cases and if a storm does breach the cap, it could be quite amazing. I think tornado chances increase a bit near sundown when the temps cool enough to perhaps lower the storm bases. Helicity and instability both seem good enough to support a rotating storm or two IF the cap can be breached.

Do I think the cap will break? I'm heading out, that says enough... but I'm definitely more than knowing of the cap and think I could easily be driving out for a meal and be back home tonight.

This was an easier day to chase when it was on the way to Thursday, but given I may end up in Maine by the end of that chase, I have elected to pass on Thursday all together. With that said, this is a one-day shot for me and given its proximity to Denver, I am gonna chance it.

Batter up...

 

[Tim Marshall]

Yes, the Goodland-McCook area is the best area to be IMO. However, looking at the morning NAM, I doubt that moisture will be as high as progged and will simply not have time to get out from under the cap. The result will be high based junkus. Farther south at DDC and east of AMA, there is better moisture, but the cap will prevail during daylight hours. So, I will sit today out. Overnight, I expect convection to develop and roar eastward through KS. tm

 

[Isaac Pato]

I say that all of us should converge in Dodge City, maybe if we all blow up at the same time we can cause some forcing on the dryline.

 

[Andrew Stoller]

Alright, I'm gonna step up to the plate. The 15z RUC has a little kidney bean going through northwest KS by 23z with a big dryline bulge, which might help overcome the cap. Mid 50 degree dewpoints already reside in southwest KS; if 60 can materialize as far north as Goodland, I think at least a nicely sculpted high based LP is possible with a limited tornado threat.

Will likely head to Scott City and adjust from there if something initiates further south.

 

[Wesley Luginbyhl]

12z 4km WRF - http://www.emc.ncep.noaa.gov/mmb/mpyle/cent4km/conus/12/

Cant put too much trust in precip models, but that is one massive cell that forms near Graden City. Mid 60 degree dew points are streaming along the eastern edge of the caprock currently and I bet they can make it pretty close to I-70 by late evening. Will likely for DDC shortly and make dinner reservations for after the bust.

 

[Jeff Duda]

12z 4km WRF - http://www.emc.ncep.noaa.gov/mmb/mpyle/cent4km/conus/12/

Cant put too much trust in precip models, but that is one massive cell that forms near Graden City. Mid 60 degree dew points are streaming along the eastern edge of the caprock currently and I bet they can make it pretty close to I-70 by late evening. Will likely for DDC shortly and make dinner reservations for after the bust.

Argh! I didn't know they ran a 12Z on that site! Where'd you find that? I've been using 00Z data all the time...

I guess on the brighter side (and this belongs in the thread for Thursday, but my initial sentence ties this post into this thread), the 12Z 4km WRF run does spit out a supercell looking thing near St. Joseph tomorrow...right in my dashed hopes chase target.

 

[Chris Allington]

Looking at mesoanalysis actually shows the area of 13C 700mb temps decreasing and some cooler air emerging off of the front range, with 700mb temps of 11C nudging into the CO/KS border region. Hopefully that trend can continue as we need all the help we can get from the cap.

 

[Wesley Luginbyhl]

Argh! I didn't know they ran a 12Z on that site! Where'd you find that? I've been using 00Z data all the time...

I was messing with the parent directory last night and saw the 12z folder. There is also a folder named v3 that seems to be a slightly different run of the 4km. I am sure someone else might know a little more about this than I do.

 

[Jeff Duda]

I was messing with the parent directory last night and saw the 12z folder. There is also a folder named v3 that seems to be a slightly different run of the 4km. I am sure someone else might know a little more about this than I do.

I'm guessing v3 refers to using WRF version 3. The most recent version (the one I'm using also) is 3.1.1. It was released a few months ago.

 

[Darren Addy]

Looks like that moisture axis is significantly east of where the models had put it. The nose of it appears to be just north of Russell, KS right now. DDC is about the western extent of it and Wichita the eastern extent.

Also, what in the heck happened to the SPC surface map page? I'm getting a broken image link on the graphics.

 

[Mike Hollingshead]

There's a bad area of low level veering/push in w/nw KS that should start to go away soon/back. Hot and dry 850s. That'll surely limit return/shunt northern half east for a while. Guessing good stuff won't clear I70 terribly easy. I hope something can fire on the northern extent of that once it starts to really move north without being scoured from above. Probably near I70 if it happens is my best guess.

97 in Liberal KS at 2!

Overall a bit torn on north or south, going nw to w NE doesn't seem to gain a heck of a ton of cooling aloft and pathetic moisture. Going south has issues, love those still very hot and veered 850s down there as well as 700s bumping back up a bit. One could fire something off that hot dl but just not sure how well it does blowing east of there given it's not warming up terribly fast east of the dl in OK or KS...at least for the capping in place and likely to hang around. Just watching that area of 850s be so veered like that into the afternoon and prog'd backing, for whatever reason I had flashbacks of the afternoon of Greensburg. Back - boom. Guess I'm just a bit scared of what might happen once most of the lower levels back more into that hot dryline. Especially given the stupid 12z 4km wrf thing. Now the 18z RUC also toying with the idea around there.

 

[Darren Addy]

Forget what I was saying about the moisture axis. That's what I get for just looking at dewpoints. Took a gander at the DDC short fuse composite and the Theta-E moisture axis is right where the models said it would be: arcing around just east of DDC and then NW to the CO/NE/KS intersection.

Nice little cumulus field already visible on satellite SW of DDC in Meade County. Currently, the CAPE there is between 950 and 1200 and Low Level Lapse Rate would indicate that the show down there may start earlier than advertised.

RUC has EHI in Central KS red-lining (actually well into purple territory) by 0z. Pratt to Great Bend looks like an area to really keep an eye on the sky this evening.

 

[Darren Addy]

Looks like we may have our first spark going off in NW Meade County KS (almost straight S of DDC) and JUST SW of Minneola. We'll see if she can get grounded.

 

[Mike Hollingshead]

I suppose somebody oughta start a NOW thread. This looks like it might be the storm of the day. Looking at spotternetwork, there's NOBODY down there. Gotta believe there are a few not logged into SpotterNetwork though. Right Hollingshead?

No, I'm elsewhere. Eyeing ne CO now. 850s backed 500 cooling coming into e CO and very backed sfc winds there, if they can stay that way. Spouts anyone?

As Imperial's ob changes. Guess the dl is just out of ne CO.