  We study the mixed local and nonlocal double phase parabolic equation
\begin{align*} \partial_t u(x,t)-\mathrm{div}(a(x,t)|\nabla u|^{q-2}\nabla u)
+\mathcal{L}u(x,t)=0 \end{align*} in $Q_T=\Omega\times(0,T)$, where
$\mathcal{L}$ is the nonlocal $p$-Laplace type operator. The local boundedness
of weak solutions is proved by means of the De Giorgi-Nash-Moser iteration with
the nonnegative coefficient function $a(x,t)$ being bounded. In addition, when
$a(x,t)$ is H\"{o}lder continuous, we discuss the pointwise behavior and lower
semicontinuity of weak supersolutions based on energy estimates and De Giorgi
type lemma. Analogously, the corresponding results are also valid for weak
subsolutions.
