Note wave cyclone centered in eastern Colorado. Approximate position of dryline shown by brown scalloped line. But surface plot below can be used to get a better position on that feature. Surface pressure falls and the general position of the surface cyclone were located in a region in which net divergence was occurring through the deep troposphere.

A very unstable air mass was circulating northward into the low across Oklahoma, Kansas and Nebraska. Some supporing graphics are included below.

Note the diffluence occurring over the eastern Colorado, western Kansas, western Nebraska and southeastern Wyoming region. This diffluence was also evident at 300 mb (not shown) and was coincident with strong divergence at that level in roughly the same region, and associated synoptic scale upward motion in the mid troposphere.

The satellite image shows developing storms east of the dryline and along and just southeast of the warm front in an area of strong warm advection (image of warm advection will appear soon). But the loop below really shows the storm development better than the static image above.

Note pendant (or incipient hook) for the storm between Goodland and Colby. This storm was a right-moving supercell and was associated with at least one tornado. Other storms along the Kansas-Colorado border also had pendants. The wind profile from the Goodland VAD was favorable for supercell thunderstorms.