The blocking pattern is back, like what we saw much of Dec/Jan this past winter.

Here on the water vapor image we can see a blocking pattern in place with an Omega block over Canada and a -NAO over Greenland.

Here is the Thursday evening upper air observation at 500mb.

And with an upper ridge in Canada and an upper low in eastern Canada, we here on the eastern US can expect cooler and wetter conditions. Highs will be droping ESE out of Canada and surface lows across the southern/central US untill this pattern breaks down sometime possibly next week.