Something I look to for support in forecasting is the Alaskan Vortex. It is a low pressure system that sits in the Gulf of Alaska and typically makes for warmer weather over the US. Recently, we have been seeing a ridge over that region. So here's the forecast for 108 hours out.
See the dark blue on the upper left hand corner of the image? That is a key player in the forecast. That is a form of the Alaska Vortex. Check out how there is a ridge (orange) stretched out into Alaska trying to make a move. This low pressure system will see the ridge and beat it down, and I expect this pattern to go on for a while, where a ridge tries to move north but the low pressure system beats it down. This ought to lead to some more active weather as the two opposing factors (ridge and low pressure system) fight each other and try to get to Alaska, which appears to be the place to be.
|12z GFS Hour 108 500mb Height Anomalies|