5/12/2010 FCST: IA/MO/KS/OK/IL

[Brandon Clement]

I kind of like today's setup across southern ks and c/w OK. There does appear to be a brief period in a narrow area in which could see a very nice combination of ingredients assuming the timing comes together as the nam and ruc are pointing out. An area from Medicine Lodge south to the red river looks like the south play. Current TD in Medicine Lodge is 66 with that creeping up into the low 70s by 00z this evening. Both the nam and ruc have a 5k cape pushing into sc ks. Shear is certainly going to be the bigger issue today. There is going to be almost no 0-1 srh until later this evening until it cranks up for a short period after 21z. By 00z the nam has 400 0-1 bullseye painted over Medicine lodge. The biggest concern here is the bullseye is very small and the values drop off quickly to the east and west.

Overnight convection should leave some outflow boundaries in the area which could increase the chances for storm initiation as well as shear. The nam, sref and ruc break out storms in the area and storm motion is very manageable so even though the better igredients are in a very narrow axis, if storms can fire in the area they should stay in it quite a while.


A couple concerns in this area. Farther north in south central Ks, linear storm modes could be an issue. Farther south, capping could be an issue. In both places the timing of the low level jet and storm initiation is going to be a concern.

I'm currently in OKC leaning towards Medicine Lodge but will probably hang out a while and see how southern Ok shapes up before taking off north.


Edit: 12z model run has lower 0-1 srh across southern ks and the 12z nam is pushing 0-1 ehi levels up to near 5 around SW Ok. The Ok play is going to be very dependent on the low level jet to increase quickly this evening.

 

[Adam Atkins]

I'm not a fan of cold frontal setups where the shear vector angle is very close to the orientation of the front. My target isn't even listed in the thread title, but I'll throw my $0.02 in anyhow.

I like the southern dryline target today A LOT. There should be full insolation all day along the dryline in north TX. Storms should fire as the departing jet streak and surface moisture convergence occurs from eastward mixing of the dryline. The RUC is showing a considerable dryline bulge near Wichita Falls and into the western Red River valley.

Cap strength is a much bigger factor in N TX than along the front from W OK up through the Mississippi River valley, however this could lead to 2-3 isolated storms developing rather than a broad scale MCS (expected further north). Low level winds will back slightly in response to height falls as the trough axis approaches and jet streak departs to the NE. Sustained supercells are a very good possibility and the combination of 3,000 CAPE/250-300 0-3km Helicity means tornadoes aren't out of the question.

My target would be between Graham and Wichita Falls, TX today.

 

[Brian Stertz]

If the LLJ was a bit more vigorous I would surely be excited about today's potential. The key will be getting good breaks to get temps. in the 70's in the WF zone. I am kind of in the same frame of mind...if it happens I'll be ready...but if it does not no biggie. With a sfc low heading this way, I think there will be a few tornadoes within 40 miles of KC...if not the immediate Metro. Intensity and duration of any tornado is the big question...at least not moving 50-60mph today. The RUC sig severe parameters suggest that there will be strong supercells for anything that can stay discrete and beefy.

 

[David Mayhew]

I'm thinking along the lines of Brandon, but locating further south to start with. Probalby going to head to Waynoka, OK. LI's and Cape look good and the dryline is progged to surge east into W OK. Question from a non meteorologist - if the cold front is expected to swing down into NW OK can this cut off storms from moisture or will it provide additional lift?

 

[Rebekah LaBar]

My blog has a full (though still somewhat abbreviated) forecast.

Suffice it to say there are plenty of problems with this setup, as has been discussed above, but as it looks like we may be ridged next week, this might be the last decent setup in the Oklahoma area for a while.

So I'm heading out within the next hour for Enid, initially, with low expectations but hoping to catch a supercell or two maybe at the end of a line, provided that there is enough forcing to break the cap and the low-level jet can provide us with sufficient shear later in the day.

 

[Scott Udell]

I forgot my Kestrel at home (doh!) so can't report direct pressure/humidity/dew point observations, but currently at Leavenworth (11:45 CST) the temps are maybe low 60s (put it this way--it's 68 in my office and colder outside), breezy, and still a lot of overcast. It's not quite as (literally) dampening as Monday, but so far it's close--clouds would have to break soon for the earlier forecasted 80 degree mark to have even a chance. I don't know about the SW KC metro area--there can be surprisingly sharp differences between Olathe and Leavenworth.

 

[Jason Haller]

I forgot my Kestrel at home (doh!) so can't report direct pressure/humidity/dew point observations, but currently at Leavenworth (11:45 CST) the temps are maybe low 60s (put it this way--it's 68 in my office and colder outside), breezy, and still a lot of overcast. It's not quite as (literally) dampening as Monday, but so far it's close--clouds would have to break soon for the earlier forecasted 80 degree mark to have even a chance. I don't know about the SW KC metro area--there can be surprisingly sharp differences between Olathe and Leavenworth.

Best i can tell the warm front is on the the move north westward and should be past leavenworth in about a hour. TOP expects thing to start going along the front about 2 pm and ride it. Hoping that Manhattan is on the south side of the front when that happens.

 

[AndrewLee]

If I could leave work early enough to get out of the KC Metro area before rush hour traffic I would probably setup in Emporia,KS and hope to hop on any discrete storm that fires and follow it back towards KC. Excluding some of the timing issues that others have mentioned, all of the ingredients are there for discrete rotating storms I just don't feel very confident that forecast will verify. My gut instinct (very scientific - i know) is that a play further south (somewhere between Medicine Lodge and Wichita) has better potential for discrete storms.

 

[Mike Johnston]

Don't know what to make of the convection that has recently popped from NE of Wichita to W of Council Grove. Storms are in vicinity of warm front and moisture convergence zone, but not exactly riding along the front. CIN is eroding in the warm sector, so perhaps there's just enough lift to get things going, albeit a bit earlier than anticipated. Convection appears unorganized as of now - and certainly no signs of rotation - with tops of 35K to 40K ft, so kept this observation in the forecast thread rather than starting a NOW thread.

Anyway, I'm still moderately bullish on the potential through east central KS up to the KC metro area from peak heating to about 02z. Just hard to ignore the boundary in place and the building instability and boundary layer moisture.

Also, note the Topeka radar now appears to reflect some type of boundary between Topeka to just north of Council Grove.

 

[Scott Udell]

Garnder, KS is at 73 with a DP of 66, while KCI is 61 with a DP of 59. Lawrence is 64/61 as is KFOE in Topeka, and KEMP in Emporia is 73/64. Still showing as overcast in all those areas except Gardner, which is showing as broken, with ceilings from 800-2100ft throughout the area.

 

[John Farley]

I'm in Forestell, MO headed for the COU area. Warm front appears to be just south of I-70 all across MO. RUC is forecasting CAPE of 3000-4000+ over a large area of northern MO by 23Z, and it breaks out isolated storms along the WF. EHI predicted to be 6 or higher. Now even if this is somewhat overdone, it looks good - though you wouldn't think it from the cloudy and 69 with northeast wind here. But we saw the other day how fast things can change, and the RUC continues to think they will, in fact getting even more bullish than it was earlier.

 

[Lee C. Bussy]

A cell in IA warned out of KDMX, almost straight west of Des Moines moving NE. Radar indicated 1.75" hail and tops to 45k. I didn't see that one coming. Audubon, Guthrie counties. VIL is ~60 but no rotation indicated.

The real question is whether to leave work early and head for St Joe.

 

[J Holder]

Mods: You can kill this in a couple hours.

FYI -Anyone coming through Topeka right now STAY OFF I70 through downtown Topeka. Currently there's a massive accident involving KHP and Topeka PD officers down (hit by cars) causing major traffic backups. Take 470 or Turnpike arounf toward the South.

 

[cstrunk]

I'm in Platte City, MO getting wifi from the Super 8. Moving southwest to Lawrence to sit at their Super 8 and get more wifi. The warm front is roughly along I-70 and doesn't seem to be moving much. Don't like that early crap-vection coming through, but it looks to be clearing behind it and CAPE shouldn't be an issue.

If anyone would like to nowcast for me, I'd appreciate it since I don't have mobile internet. PM me and I'll get you info when I find internet again. Thanks.

 

[cdcollura]

Good day all,

Sitting here west of Wichita (ICT) and watching start of agitated cu field to my west. SPC also issued MCD 527 for this area with possible issuance of tornado watch box.

There is a weak surface low near Woodward, Oklahoma and a stationary / cold front extends from the low to near Kansas City. Cap is eroding and good heating (RUC has CAPE as high as 4500 south of ICT in a bulls-eye like feature by 21z.

I see SRH around 150 in the area but I am a bit concerned (and suprised) to see a "hole" in the SRH plots west of ICT by 21z on the RUC (rather strange?).

I still think east and north of Wichita Kansas should be good play for initial storms before all goes linear near dark.