I am liking the setup for Friday more and more with each run. The deep layer shear is impressive at/above 50 knots BL-6km shear and 30+ knots 0-1km shear on the 12z ETA. Instability and strong shear looks supportive of intense supercells and tornadoes, particularly across C/E Iowa in the vicinity of the boundary. As with much of the IA severe wx events of this spring, these have been centered on the Iowa City/Cedar Rapids/Davenport corridor. This particular area looks like it may get hammered again Friday.[/b]
Update of tonight's 00z ETA/WRF...shows that the more significant severe wx theat has shifted further northwest than previously forecasted. Both models were indicating a corridor of good instability and deep layer shear across W. Iowa. The BL-6km shear while not as impressive as the 12z run, but was still showing 40+ kts. across much of W/C Iowa with 2000-2500 j/kg ML CAPEs focused between Sioux City IA and Omaha NE. It looks like the probable window for tornadic supercells over extreme E.Nebraska/W.Iowa will be open after 5pm and probably start shutting down shortly after sunset when a MCS cluster or several clusters organize becoming elevated with time.