Though the Winter of 2009-10 was slow to come on (as opposed to last winter), thus far this winter has been fairly typical (through December). This spell of well below normal temperatures since the beginning of the New Year has been potent but certainly not record breaking. Look for next week’s temperatures to moderate back up to at least the 30s. It is a bit early to say if this will constitute as our January Thaw but it will definitely be an improvement. January Thaws are loosely defined as a period of mild weather popularly supposed to recur each year in mid-late January. Many January’s contain a milder spell of weather across Southeast Lower Michigan anyway, but it doesn’t have to be a full fledge thaw. Next week does look promising for a moderation in temperatures and break in the deep freeze as the coldest of air retreats back up into Canada.
All models are showing this break in the cold next week to varying degrees, check out the projected upper jet from GFS model midweek. It shows the Arctic jet stream cold retreating back into Canada as weak upper high pressure pushes into the Midwest bringing milder temperatures while the sub-tropical jet (aided by El Nino) remains active.