Yeah, it hasn't been a -NAO in the technical sense, but on balance when looking at the May & June maps, there has definitely been pretty stubborn ridging west of Greenland towards Hudson Bay (kind of emulating the look of a west-based -NAO).
Of course, paired with what has been fairly persistent troughing on the west coast into the GOA, the duration of troughing and cooler weather for the eastern half of the country has been transient.