7/22/10 FCST: IA/IL/WI/MI

[Dan Thompson]

I am wondering if anyone is going after this one today. The 12Z NAM paints a decent picture around the Dubuque, IA area, with no cap and up to 3,000 J/kg CAPE along with southerly surface winds. Of course that is if the sun manages to come out after the morning stuff goes through/weakens. The HRRR fires off convection in NE IA beginning around 19Z, but the RUC/HRRR show more veered surface winds in this area. Any smart people care to comment?

 

[ahaberlie]

The ongoing morning MCS is in the process of creating a well defined boundary that should be the focus of convection later this afternoon. On and north of a line from Waterloo. IA to Janesville, WI should be a good area today.

Models are great.. but just look at where the boundaries are being defined *now*.

 

[Joe Zagrodnik]

Hey Dan!

Looks like the MCS has cleared out nicely. Most of southern IA is clear, with ML CAPE approaching 1,500 J/kg already. Looks like things will fire along the tail of the LLJ. Best chance of a tornado is right on that boundary.


Based on the vis satellite, I would go to Waterloo and re-evaluate from there.

 

[nickgrillo]

Interesting situation... Current RUC mesoanalysis shows extremely supportive kinematic profiles across the warm sector, with rich boundary layer moisture boosting surface-based and mixed-layer parcel CAPE 1000-2500j/kg along and south of the surface warm front in southern MI. Worried about the TOR-warned storm (in sw MI) as it crosses into the "cool" sector, but at least sbCINH hasn't really strengthened much given the mechanical mixing, which has helped to reduce nocturnal boundary layer de-coupling. Assuming boundary layer-based storm inflow layers, I could see the potential for tornadoes with any sustained convection given the extremely intense near-ground shear invof the warm front.