The Hudson Valley is a 10 county region designated by New York State that stretches from Albany County down through Westchester.
The "Upper Hudson" portion of the valley includes the Capitol District, consisting of Albany, Columbia, Greene and Rensselaer counties.
The "Lower Hudson" portion of our area includes Putnam, Rockland and all of Westchester counties.
Most people, it seems, confuse the Hudson Valley with the "Mid-Hudson" portion of the region. Dutchess, Orange, and Ulster counties are all considered part of the Mid-Hudson region, which sits in the middle of the Hudson Valley.
Sullivan County, although not officially on the New York State map of the Hudson Valley, is widely considered a part of the region. Small portions of the Catskills bordering Green County are also considered part of the Hudson Valley.
So, while it's true that Albany and Westchester are not in the "Mid-Hudson Valley," they are most certainly a part of the Hudson Valley. In fact, Ulster down through Westchester is usually lumped together as "Downstate New York" with the Upper Hudson Valley and all counties north being classified as "Upstate."