5/25/08 FCST: WI/IA/MN/IL/KS

[Mike Johnston]

Dryline definitely retreating westward over Kansas, and RUC runs suggesting a juxtaposition of ingredients in western Kansas in the 22z - 0z time frame; not only the surface low developing over E CO (which should encourage a wave along the dryline), but also notice also by 00z how the 20-30 kt 850 flow is backing out there.

I note Jeff's concerns about the dry air over western OK. However, this hole looks like it is being encroached from both the east and west w/ time. If you loop the theta-e charts on the mesoanalysis, you can see the hole waning and hopefully in a few hours it will simply be overcome.

Now, I would target the western edge of the moderate/hatched area, and even go a little further north than DDC, say the Ness City-Scott City-Wakeeney vicinity. Moisture/instability looks great there, closer proximity to stronger mid and upper flow, LCL's and LFC's should be a tad more reasonable than points further south, and more oriented w/ good backed winds at the surface.

 

[Adam Penney]

Well I am unable to chase today, but will leave later this evening for SLN to be in place for tomorrow's chase. If I were chasing today, Id like to be in the area from Great Bend to Dodge City,KS. 850 winds along that line over to DDC back up to around Oakley appear to be backing around 25-30kts. 500 mb flow is good, and shear 3km shear profiles are not too shabby. This area appears to stand good tornado chances today.

Good luck to everyone today, and see you out there tomorrow!

 

[Alex Lamers]

As this has more to do with the overall setup, I'll post it here. Starting to like the setup a little better for Southern Minnesota. Just did an objective analysis and looks like a nice little boundary, pretty discrete but there nonetheless, extends from S MN ese into S WI. In fact, it seems to be reinforced well by the cool outflow from the earlier thunderstorm complex to the north.

Meanwhile, deep moisture making good strides off to the northeast. 60F isodrosotherm now pretty much at the Mississippi River. Dewpoints in the area along the Mississippi River have increased ~10F in the past 3 hours or so.

Would expect initiation as low level lapse rates steepen later into the afternoon where thetae ridge is nosing into S MN and near where it meets the boundary...probably somewhere between Marshall and Mankato.

12z NCEP NMM run (4km) of the WRF shows this pretty well and then an extensive line of storms developing and riding the boundary into NE IA...SW WI...and N IL after 00z.

Will be interesting for sure. Enough shear present for some supercells initially and then eventually the mode should be increasingly linear. I won't be driving to Minnesota...but if I were closer I'd set up somewhere on I-90 west of Albert Lea and wait for a few hours.

AJL