4/24/09 FCST: MN/IA/WI

[Chip Redmond]

I really wish I could chase this weekend but will just have to hope for a midweek setup in the Ohio Valley or another good weekend next week in the plains. Anywho...

As of right now I would pick a target area of Cedar Rapids. NAM is actually now plotting a near bullseye of 2500+ j/kg from 18z on. Strongest frontal forcing will still be farther west preventing anything from going immediately linear if it can get going early. Directional shear is definitely there and forecast hodographs support right turning supercells although more speed shear would help greatly. I would like to see some improvements in helicity as best values of 100+ are much farther west and slightly farther east. One thing that really has caught my eye is the MCS/MCV that is currently passing over Chicago. It passed just S/SE/E of my would be target area through the course of the evening. Winds in its wake and vicinity are relatively calm (hence the dense fog advisories) which may play an important part in the lack of mixing. A fairly prominant boundary may have been laid from a line extending from St. Joseph, MO NE to Chicago. This boundary will be most visible as day comes around and may play a very important part of initiation and the possibilities of storms to become tornadic despite the lack of variables from the synoptic setup. Just a few thoughts.


Chip

 

[Josh Richardson]

As mentioned in my last post I would get to chase my backyard for this one and still obviously like this area best, going to make a pretty leisurely chase with targeting between Mason City and Clarion IA for this or maybe just a few miles west of this line. Most other specifics have been mentioned above so we'll leave it at that.

 

[Jeremy Den Hartog]

Okay, I have been convinced. We are heading to north central Iowa towards Algona or Dakota City...thanks guys for the input

 

[Jeff Duda]

The 06Z models are lagging on frontal position. If I go (it seems likely I will), I'll have to adjust my target further downwind.

 

[Aaron Gerhardt]

Tim and I are going to head out to Western Iowa later today.

 

[Andrew Revering]

I like Clarion, IA @ 6pm.

 

[Rob H]

I have a gut feeling about waiting a little more east, nothing concrete to back that up with though... if I decide to pull the trigger on this chase, I'm thinking of setting up shop in Hampton. The close proximity to 35 and 20 will be nice. I just need to decide if I can afford to blow off afternoon meetings at work.

 

[Paul Redmond]

Me thinks that central and northeastern texas should also be entered into the discussion, as SPC just issued a mesoscale discussion for this area. It appeares a severe weather watch may be issued shortly in this area as low level moisture and lapse rates are becoming sufficient for stronger storms and possible isolated supercells. Hmmmmm. Luckily for me I brought the chase kit today.

 

[W. Grant Dade]

I would have to agree Paul. CAPE over 2000 J/kg and 0-3km EHI above 5 in central TX right now. A nice little suprise with the SW moving through now. Look for a tornado watch soon.

 

[W. Grant Dade]

Surface based convection having a hard time in central TX. Will see what happens when 500mb cold pocket moves over central/east TX over the next couple of hours.