The forecast challenges this week can easily be summed up by Fridays forecast Moderate risk in Oklahoma and the extension of increased risk through IL. That was our area of focus. We had the full complement of model guidance, and some experience from days prior about how difficult it is to have confidence in making good areal forecasts and then putting the probabilities in the right 3 hour time windows.
Tuesday, May 28, 2013
Thursday morning we awoke to a line of thunderstorms across central OK. Eastern CO had what appeared to be a cold air dam and to the east southeast appeared to be situated a deformation zone. Given the stronger deep layer shear, this small area of convection intensified an a southward moving supercell developed around 12 UTC. This cell and its previous incarnation had dropped a bunch of hail (drifts near Blanchard, and larger hail with the supercell).