Now here is a trend loop of the last 16 runs over the past 4 days of the GFS Ensemble Mean for Jan 28 (at day 10). The axis of the western ridging has trended east with it initially more thru Alaska, but now it's closer to the W Canada coast. This is a good position in between pure Alaska ridging (-EPO) which can sometimes be too far west (sometimes the U.S. trough can be too far west), and pure Western Canada ridging (+PNA) which can sometimes be too far east (cold, but sometimes on the dry side). Also, the polar blocking on the trend loop has waxed and waned, but the latest few images show a bit more Greenland blocking (-NAO).