A strong polar jetstream is one of the reasons for our mild winter across the United States–it’s kept the coldest of the air locked up in Canada and has protected the lower 48 from any long-lasting cold air intrusions. It’s been a different story for areas where the cold air has been locked in such as Alaska which just had one of their coldest winters in years. The arctic air intrusions into the lower 48 usually mean they have mild air intrusions into Alaska–and they’ve been just as absent up north.
This trend of mild air will continue for the foreseeable future with only a few bouts of chillier air over the next 10 days. Take a look at the upper air pattern through mid March: