We calculate the finite-temperature local mixed Hall coefficient of gapped graphene in a clean, noninteracting Dirac model. It relates a deformation-induced pseudo-electric field to a transverse charge current. Fermi occupations round the zero-temperature band-edge cusp into a crossover whose normalized line shape is fixed by $T/|m|$ and $\mu /|m|$, where $2|m|$ is the gap. The insulating plateau is exponentially stable away from the edge. In a window of order $T$ about the band edge, the leading loss of plateau weight is $(T/|m|)ln[1+exp((|\mu |-|m|)/T)]$. Farther into a band, the leading thermal correction increases the magnitude of the response quadratically in $T$. We apply this result to two previously proposed drives, a traveling flexural wave and a dynamic phonon mixed with a static ripple. Their second-harmonic and fundamental-frequency signals probe the same intrinsic thermal dependence. We also give the electrostatic mapping needed to compare this prediction with gate-voltage sweeps.