  We introduce a~paraconsistent modal logic $\mathbf{K}\mathsf{G}^2$, based on
G\"{o}del logic with coimplication (bi-G\"{o}del logic) expanded with a De
Morgan negation $\neg$. We use the logic to formalise reasoning with graded,
incomplete and inconsistent information. Semantics of $\mathbf{K}\mathsf{G}^2$
is two-dimensional: we interpret $\mathbf{K}\mathsf{G}^2$ on crisp frames with
two valuations $v_1$ and $v_2$, connected via $\neg$, that assign to each
formula two values from the real-valued interval $[0,1]$. The first (resp.,
second) valuation encodes the positive (resp., negative) information the state
gives to a~statement. We obtain that $\mathbf{K}\mathsf{G}^2$ is strictly more
expressive than the classical modal logic $\mathbf{K}$ by proving that finitely
branching frames are definable and by establishing a faithful embedding of
$\mathbf{K}$ into $\mathbf{K}\mathsf{G}^2$. We also construct a~constraint
tableau calculus for $\mathbf{K}\mathsf{G}^2$ over finitely branching frames,
establish its decidability and provide a~complexity evaluation.
