7/10/09 FCST: KS/MO/IA/IL

[John Farley]

As with most days with decent potential in this area this year, I am limited in when I can chase tomorrow, since I have an opening reception to attend 5-8 p.m. for a show in which I (ironically) have a storm photo. To me, tomorrow looks like another one of those hard-to-read situations we have had several of in this region this year. I am sure there will be severe weather, and I think it is likely there will be some supercells and probably at least a tornado or two. But picking out where, with so much convection all over the place and as much model disagreement as there has been, won't be easy. Based on this evening's NAM run, I would think the best place to be would be somewhere along the MO-IA border, and probably fairly early, like between noon and 4 p.m. There are certainly areas with very good CAPE and shear, and directional shear is certainly going to be there. Probably too much, actually, with almost 180 degrees from the surface to the upper air, per this evening's NAM run. And there is a question as to whether the best shear and instability will coincide, and of course what effects overnight and morning convection will have. The earlier part of that 12-4 time frame might actually work for me/ If I did not have to be back by 5 or 5:30, I'd definitely be chasing. And I may be anyway, if I like what I see in the morning.

 

[Brian Stertz]

Things look quite good on 00z NAM for supercells just east of KC if something can break the cap. EHI's of 10+ with managable cinh Friday evening. Not sure if anything will be able to get cooking supercell wise on KS side. Cap is pretty fierce & hot. Something to monitor around suppertime....maybe hang out and wait over towards Higginsville or Warrensburg MO.

 

[Eric Flescher]

Might be more then a B day today in two target areas

Happy B day Danny!!

I am surprised there is not more chatter on this thread part as of late about 7/10 potential.

Two bulleseye areas to choose from (Via SPC)

(1) Western KS, Western NE, Western CO, Eastern south Wyoming with 5% tornado potential and 30% hail outlook (is it just me or hasn't there been a lot of activity lately in this area?)

and

(2) West MO, East KC/NE/IA
2% torn potenial
15% hail

Since I am closer to (2), packing to go to China to videotape and photograph the next Total Solar Eclipse -TSE (anyone else going? PM me) and want to stay close and use my time wisely before I leave, I choose (2).

I will look at all the other stuff later if I have a chance. While I am getting better at reading the NAM and other forecastingtools etc, heck at this point, many of you all are much better at reading the prognostications.

I think Brian has a good idea and I will head towards Kansas City later today and maybe further west . How far to Warrenburg etc we shall see.

(PS sorry if this forecast is less then stellar in terms of forecasting jargon etc)

 

[Brandon Sullivan]

Convective scenario still playing out relatively like I expected. Remnant MCS from IA/MN that fired last night continues to move east, and is turning southeast in response to the mean upper level flow.. Another area of precip that formed inv of an instability axis in western misourri continues to move east as well. More storms are also firing now again over Northwest Iowa, in response to an increasing warm air advection along an instability axis, and increasing ascent associated with the southerly low level jet. These areas of thunderstorms are seperated by a stationary boundary stretching across MO. The RUC continues to have the best handle on the ongoing scenario, so will rely heavily upon it for the forecast this afternoon.

Clouds from rolling MCS to our south are spreading northeastward and expect them to continue.. No real strong signals of any notable dry air to work with, as far as being able to erode cloud cover. The evolution of said systems is critical in the coming hours, to the amount of instability noted this afternoon. Ultimately determining if severe weather occurs later today. RUC continues to indicate that MCS activity should diminish as SBCIN increases and storms become increasingly elevated.

If potential instability can be realized, and storms can fire along residual boundaries in eastern iowa later today, then they should become severe, with favorable upper level support and wind fields. UA winds are nearly perfectly aligned perpendicular with the sagging frontal boundary which should promote scattered activity longer, before activity congeals into an MCS..

Current plan is to watch movement of the said boundary across northern mo, and the outflow boundaries from morning systems.. Impressive shear along this boundary could produce the storms we want, again if clearing occurs!

 

[Bob Hartig]

Woke up this morning and looked at the RUC...
Hmmm...sounds like the first line of a blues tune, and I guess that's pretty much what it is. Any ideas about an Illinois chase have evaporated. Good instability and CAPE aren't connecting. The national radar composite and GOES really tell the story, with that killjoy of an MCS dominating the scene. Guess I'll stay at home and keep an eye on local developments throughout the day. At this point, Michigan looks as good as anywhere else I'd be willing to drive to, and here in Grand Rapids, at least I'm on the fringe of functional H5 winds.

 

[Ryan Wichman]

As of right now, it appears that the last MCS of the morning is moving through central Iowa right now. IF the atmosphere is beginning to warm and kill these storms we should start to see a decrease in storms in central and especially western IA/MO. This should allow the atmosphere to destabilize nicely this afternoon under the decent cap which is developing.

I believe that this afternoon storms will develop once agian under peak heating, but more likely on OFB's and weak surface features. These features will allow for local backed winds briefly, justifying a tornado threat. But with the largely unidrectional flow it looks like a nicely organized MCS or two will develop and plow over Eastern IA/MO and move into IL.

 

[Mark Sefried]

Don't see much of anything happening later today over Eastern IA and IL as there will be subsidence on the back side of the mcs that is currently over Eastern Iowa. Cloud cover/ precip with that mcs will limit the instability over the region as well.

 

[Scott Weberpal]

Looks like the evolution of the MCS is precisely how the NAM/WRF showed last night, unfortunately. Still holding out a little hope that the cloud debris in Northeast IA will clear by mid-afternoon yielded an outside shot at a supercell across N. IL into WI where the best deep-layer shear will be residing.

 

[John Farley]

I would think the area with the best potential would be along the outflow boundary from the MCS now in southeast Iowa and northeast Missouri. If I am reading the satellite imagery right, that outflow boundary is now surging southwestward into a relatively clear area in north central and northwest MO and extreme southwest IA. Given this clearing and movement, I would think that somewhere near the Kansas City area in northwest or west-central MO or maybe extreme northeast Kansas or southeast NE might offer the best opportunity. RUC is forecasting EHI of as high as 10 in parts of western MO this afternoon, but of course it will have to stay clear - an uncertain prospect for that to happen. But if it does, there could be some real potential in this area.

I am assuming that the strong storm at the west end of the aforementioned MCS now crossing from IA into MO will weaken in the next couple hours, but if that should not turn out to be the case it will also offer some potential given the good shear over much of MO. Anyway, it is not looking like I am going to be able to chase given my commitments later today, but if I could, I would probably head west on I-70 toward the KC area but keep an eye also on that storm up north for at least the next hour or two.

 

[Chris Koetters]

Im starting to wonder if NE Missouri may be the best place to be if it can get out the cloud cover soon? RUC is pushing good CAPE and LI's up into the area, and if I remember correctly eta was having the llj start to nose into that area around 18z. And for cap, that area is right on the edge of the higher 700mb temps.

 

[Ryan Wichman]

John and Chris, you read my mind.

I have always liked NE MO/SE IA for the main reason that OFB's will be present. After this MCS/rain crap moves through the Quincy area here, we should quickly dry out and see some clearing develop. If anything the rain early this afternoon has allowed for surface DP's to increase and the inhibition should keep storms from firing up right away this afternoon. Instability should be on the rise here in the next few hours and looks like the wind fields are starting to line up right. I still think there is a good shot, not just an outside shot that we will see a tornadic storm in this area.

 

[Brandon Sullivan]

Im calling it an evening.. Although I live in Western, IL and can go locally if need be.. This is why..

Stable Air.... Yes, CAPE values are rising rapidly in response to the ERODING clouds.. These clouds are dissipating in response to subsidence (sinking air behind the morning activity ) CAPE values may be pushing 3k but negative vorticity advection (NVA) on the back side of remnant MCV is killing our shot at getting any activity. CAPE has no effect unless a parcel can reach the LFC, which right now is highly unlikely, thus even 3k CAPE can be called a stable atmosphere in such cases, like right now..

Chalk it up to '09.... now... who wants uplsope!!!