Sunday, May 8, 2011

5/8 - 7:30am CDT - Heading North This Morning

We'll most likely head north to either Northern Kansas or Southern Nebraska as the severe weather setup in that vicinity seems to be shaping up rather well. The SPC has issued a Slight Risk for most of Nebraska and South Dakota, with a little bit of North Kansas thrown in. A 5% tornado risk has also been issued for this area. An eastward push of the dry line and easterly surface winds up that way should fire off rotating supercells this afternoon provided that enough moisture makes its way northward as advertised on the computer models this morning. A batch of rain is currently moving through the north and east portion of Nebraska, but that should not contaminate our target area.

LCLs (cloud bases) will be very low in North Central Kansas and most of Nebraska, which is always a good thing for tornado development (click right image for LCL forecast). Upper-level winds are not terribly strong (30-35kt at 500mb), but that should be enough to get things going. Storms that form may only move at 10kt this afternoon according to the 6z NAM, and that coupled with about 40kt of bulk shear should make for a batch of slow-moving supercells. CAPE or instability values of over 3000 J/kg will also be crucial to the development of these cells today.

Should anything change dramatically in our target area plans, I'll post a brief update here from the road. Don't forget to follow me on Facebook and Twitter for all the latest reports and photos while we're chasing!

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