April 9th, 2011 - Chase Forecast Blurb - IL/IA

Very interesting couple of days on tap for the area. When I say things will be interesting that won't bode well for those who like sunny warm weather. Tomorrow may be one of those days where I get a sun tan, but could also be one of those days where Iowa likes to lure unsuspecting chasers away from Illinois magic. As it looks right now I will be playing the west-central Illinois area near Quincy for supercells. There may not necessarily be tornadoes, but a nice storm will do the mind and body good. Latest check of the models gives me a fairly easy target. Both the NAM and GFS show a bullseye of 4,000 CAPE near the tri-state area and with LI pushing -9 the atmosphere will be cooking. Like last weekend though the question is whether or not a storm can break the cap. The NAM LSI shows a big hole where the cap eroded at 0z in the area of 4,000 CAPE. With this area being just south of an advancing warm front, I think it is a safe bet to say we could be looking at a storm in an area being shadowed by the more substantial risk in W IA. SBCAPE in the area will be over 5,000. Soundings aren't the worst I have ever seen (WEAK SURFACE FLOW :( ), but if you can get over the fact that it will be capped tomorrow for a majority of the day, you may find yourself a lone of a dirt road in W. IL watching TCu blow.

Chase target: Carthage, IL
Official forecast: A storm or two pops between 22-0z, explosive development seems possible. Storms move at manageable speeds but with little surface flow I am expecting more of a hail threat. If a storm can blow near the warm front, watch out for a few tornadoes. The T/Td spreads are better than last Sunday (I have seen some models hint at 78/70) so that is a plus. However, if 5-10 kt sfc flow is the best we can muster, it is going to take one strong supercell to be able to put down any appreciable tornado especially the further south you go from the frontal boundary. I will be out getting a sun tan tomorrow. Will you?