We summarize and combine direct measurements of the mass of the $W$ boson in $\sqrt{s}=1.96\text{ }\text{ }\mathrm{TeV}$ proton-antiproton collision data collected by CDF and D0 experiments at the Fermilab Tevatron Collider. Earlier measurements from CDF and D0 are combined with the two latest, more precise measurements: a CDF measurement in the electron and muon channels using data corresponding to $2.2\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ of integrated luminosity, and a D0 measurement in the electron channel using data corresponding to $4.3\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ of integrated luminosity. The resulting Tevatron average for the mass of the $W$ boson is ${M}_{W}=80387\ifmmode\pm\else\textpm\fi{}16\text{ }\text{ }\mathrm{MeV}$. Including measurements obtained in electron-positron collisions at LEP yields the most precise value of ${M}_{W}=80385\ifmmode\pm\else\textpm\fi{}15\text{ }\text{ }\mathrm{MeV}$.