Measurements of differential top quark pair production cross sections are presented in the single-lepton decay channel, as a function of a number of kinematic event variables. The measurements are performed with proton-proton collision data collected by the CMS experiment at the LHC during 2016 at $\sqrt{s} = 13\,\mathrm{TeV}$, with an integrated luminosity of $35.9\,\mathrm{fb}^{-1}$. The data are compared to a variety of state-of-the-art leading-order and next-to-leading-order top quark pair production simulations.