By mulchatna on Wednesday, January 09, 2008 - 01:45 pm: Edit Post
In winters past (in Minnesota) it seemed like we would have a pattern of Alberta clippers. These fast moving storms would dump 2-6" and then very cold air would follow. What is the atmospheric setup for this and why haven't we seen this happen lately?
By admin on Thursday, January 10, 2008 - 12:08 pm: Edit Post
Seems like true Alberta Clippers have been a bit rare in the past few years, not sure why. Just one of those things where we cannot explain the longer term weather happenings. However, there is the potential that the type of pattern that produces them may be setting up later next week or perhaps into the Jan 20-27 period.
That upper air pattern consists of a weak ridge across the western US, with a trough in the eastern 1/2. That puts the Midwest in a flow out of the NW. You do not want the ridge in the west to be so strong that the pacific storms cannot penetrate it or ride over it and become clipper systems into the Midwest, but a ridge in the west and a trough in the east is the ticket.