8/10/07 FCST: MN/ND/SD/IA

[Beau.Gjerdingen]

Surprised we are not seeing any chatter on this already. Looks like a fairly decent shortwave passing through the upper midwest tomorrow. Nice deepening low all day as depicted by both NAM and the GFS. Strong frontal boundary setting up by midday across northern SD and into Western Minnesota, with excellent moisture pooling up. Lapse rates steepen up with the arrival of the shortwave leading to excellent destabilization. The kinematic setup appears to be one of the best we have seen in several weeks with some actual mid-level flow to speak of! Looks like a plenty good environment for tornadic supercells, especially given the good low level flow and large hodographs near the boundary. Main questions appear to be the strength of the capping, and the storm evolution from supercells to a large severe complex. Right now my main goal is to find a way out of work early... which appears right now to be a difficult task for tomorrow!

 

[Tony Perkins]

I fear the rather ominous cap in this setup. Target: Redfield, SD to Watertown, SD.

 

[Derek Weston]

Potentially looking like the best setup this summer IF the cap breaks. I'd be sitting in E. Central SD tomorrow if I were chasing.

We've even got a lil bit of 500 flow going again. Very good shear profiles.

We shall see... I'm thinking that we've got to come out on the lucky end of one of these setups sometime here...

 

[Dave Winslow]

I agree with the others about the ingredients, looking good in most respects. One thing I don't like though is how crummy the morning DPs are compared to yesterday with worked over air in NE and IA. If we had yesterday's moisture we'd have less capping issues, lower LCLs, fatter cape, etc.

There is good juice down in N. Missouri, but the question will be whether or not a developing LLJ and good 15-20 kt surface winds can pump it in. One thing we have going is the recent rains over the much healthier crops. I would also like to see a better warm front, so far it doesn't look like an excellent boundary. Right now I would target NE South Dakota, but this is with 3 hrs of sleep after a Oneill, NE chase.

 

[Brian Stertz]

Looks like the Aberdeen SD area (or maybe a bit further west and southwest initially) for today's big show....4500 ML CAPEs...strong directional shear...and 40+ kts. at 500 mb west flow. Looks like the 12z ETA also shows a slight weakness in the cap in this area. That would be my target for today...if I could chase that is. The key is to jump on the supercells early on this time of the year.

 

[kenny_allen]

Aberdeen, SD

Morning storms are moving out. We are expecting clearing and nice daytime heating. -- Clouds not moving out as fast as we want right now. SPC has moved the slight risk area further south and reduced tor chances. Target: Watertown to Huron area. Still expecting a good day.

 

[Ryan Pfannkuch]

Its noon and I'm still pondering things in Yankton SD after chasing northeast NE yesterday...obviously wishing that today looked a little more clear cut.

Not surprised at all by SPC dropping the TOR probs to 5% given the capping concern and uncertain effects of ongoing convection. I think I've finally convinced myself to wander up to the Watertown area and hope for the best. Paying homage to a fairly trusty rule of thumb, I refuse to be west of the 12C line at 700mb at 0z...and the 15z RUC depicts the 12C line running from Sioux Falls to Aberdeen later today...so I am going to hedge a little east if anything.

It's almost impossible to talk myself out of a setup this time of year that features 40-50 kts of deep layer bulk shear.