We study asymptotics of q-distributed random lozenge tilings of sawtooth domains (equivalently, of random interlacing integer arrays with fixed top row). Under the distribution we consider each tiling is weighted proportionally to q vol , where vol is the volume under the corresponding 3D stepped surface. We prove the following Interlacing Central Limit Theorem: as q → 1, the domain gets large, and the fixed top row approximates a given nonrandom profile, the vertical lozenges are distributed as the eigenvalues of a GUE random matrix and of its successive principal corners. Our results extend the GUE corners asymptotics for tilings of bounded polygonal domains previously known in the uniform (i.e., q = 1) case. Even though q goes to 1, the presence of the q-weighting affects non-universal constants in our Central Limit Theorem.arXiv:1703.07503v2 [math.PR] 5 Apr 2017 4 Often referred to as the Gelfand-Tsetlin polytope. Note that it depends on the fixed top row L K .