Both (00/12/00 Z) Eta and AVN model runs are in general agreement with the movement and intensity of two short waves throughout the period. Labeling on each of the product loops shows short wave axis positions analyzed using the GOES 6.7-µm channel water vapor (WV) imagery. One short wave, hereafter referred to as short wave #1, moves across the CWA during the period, generating only light orographic snows over the Cascades and northeastern Washington mountains. A stronger short wave, hereafter referred to as short wave #2, is approaching the Washington and British Columbia (B.C.) coast during this period.

A more careful comparison between model vorticity fields and the GOES WV imagery towards the end of the period indicates that short wave #2 is perhaps somewhat faster and further south. Notice that the difference is more evident with the Eta model output. This small difference may be the first hint that the impact of short wave #2 will be somewhat greater on Spokane's CWA.