We present calculations of various electroweak response functions for the ^{16}O nucleus obtained using coupled-cluster theory in conjunction with the Lorentz integral transform method. We employ nuclear forces derived at next-to-leading order and next-to-next-to-leading order in chiral effective field theory and perform a Bayesian analysis to assess uncertainties. Our results are in good agreement with available electron-scattering data at |q|≈326 MeV/c. Additionally, we provide several predictions for the weak response functions in the quasielastic peak region at |q|=300 and 400 MeV/c, which are critical for long-baseline neutrino experiments.