Changes in the jet stream will ease the cold in the next week

The cold that has griped much of the U.S. will begin to ease a little in the coming days.  Temperatures will still stay below average, but at least we'll be in the 20's versus the single digits!

For the majority of the winter, the jet stream pattern has been locked in place.  A ridge of high pressure in the west up through Alaska has forced a lot of the cold air in the Arctic to become dislodged and travel south into the Plains, Midwest and South.  Another ridge in the North Atlantic has not allowed for much movement within the jet stream which has kept the cold sticking around for quite some time. 

That pattern, however, is going to change.  Winds within the jet stream are going to turn a little more west to east versus northwest to southeast which will pull in a little more 'mild' Pacific air rather than the true Arctic air.  What this will do, however, is set up a little more of an active storm track across the Plains and Midwest for fast moving storm systems.  The first of those will come through Thursday and then again Friday night/Saturday.  Going into next week the jet stream pattern will change even further with a trough building across the west (rather than the ridge) and more of a southwest to northeast flow across the Plains and Great Lakes.  While warming temperatures aren't too likely with this pattern it does set up the potential for strong storm systems to move in from the southwest.  These systems are able to work with the cold air to their north, but also the moisture from the Gulf.  There have been signs of such a system coming in sometime during the Tuesday/Wednesday/Thursday time frame of next week, but unfortunately with pattern changes like these, the models have a very difficult time with the forecast and trying to forecast anything beyond three days become a little more challenging.  What we do know is light snow will be likely Thursday with a cold front.  Low pressure then developing along that front Friday will track northeast and could bring a little more accumulating snowfall Saturday afternoon.