Caption: +Dynamic tropopause (DT) pressure (shaded according to the colorbar in mb). DT=2.0 PVU surface. +925-850 mb layer-averaged relative vorticity (solid contours every 2.0x10-5 s-1 starting at 2.0x10-5 s-1). +DT-850 mb Wind Shear (half barb=5 knots, full barb=10 knots, pennant=50 knots). +Image was generated from 1.0x1.0o NCEP GFS final analyses.