We combine searches by the CDF and D0 Collaborations for a Higgs boson decaying to ${W}^{+}{W}^{\ensuremath{-}}$. The data correspond to an integrated total luminosity of 4.8 (CDF) and 5.4 (D0) ${\mathrm{fb}}^{\ensuremath{-}1}$ of $p\overline{p}$ collisions at $\sqrt{s}=1.96\text{ }\text{ }\mathrm{TeV}$ at the Fermilab Tevatron collider. No excess is observed above background expectation, and resulting limits on Higgs boson production exclude a standard model Higgs boson in the mass range 162--166 GeV at the 95% C.L.