6/1/10 FCST: NE/IA/MO/IL/WI

[Mikey Gribble]

Here is the link to the forecast sounding with the NAM for Falls City, Nebraska, which is the far southeast corner of the state. That is about where the NAM shows convection at after 00Z. There are some pretty solid paramaters there and it is definitely supportive of tornadic supercells. Supercell Potential is 93%, 260m2s2 0-1km SRH and the hodograph is pretty impressive given the strong instability.
Two things stick out a bit. One is LCL heights being moderately high, but definitely managable. The other thing that sticks out like a sore thumb IMO is the 10km SR winds around 5kts. Really... 5kts. The hodograph is sufficiently large, but we may be dealing with some wet storms.
I am still just starting to look things over, but I'm really happy with what I'm seeing so far when consider the crap the NAM was showing earlier.

 

[Brian Jalas]

This set up does look a lot like April 5th of this year except I won't be present to strengthen the cap this time so there will probably be a few tornadic supercells! I found it interesting how SPC was not even mentioning a tornado threat until the 1630z day 1.
I like those 0 to 3 km EHI's over 10 in Northeast Kansas and Southeast Nebraska on some of the model runs. A supercell riding that would be perfect for those who are out chasing today! Good Luck!

 

[Andrew Stoller]

The icing on today's cake is a large outflow boundary visible on composite reflectivity advancing from the convection in northern NE, to the southeast rapidly. As long as any grunge convection remains limited, this boundary will be present along or south of the I-80 corridor into southeast NE/southwest IA in the 21z to 00z timeframe. Wouldn't be surprised if this boundary acts as a focusing mechanism/initiation point later today with strong convergence along it/reinforcing the main synoptic front.

 

[Travis Klanecky]

Andrew...really eyballing that outflow boundary as it pushes south as well. Storms have already formed along it in an area of lower dew points in Northern Nebraska. Curious to see how it interacts with the atmosphere set up in Central and Southern Nebraska with more low level moisture. Sitting here in Hastings it almost feels like soup outside.

 

[Walter Blizzard]

Tornado warned storm SE of Norfork

Storm on outflow SE of Norfolk, NE just went torn. warned.