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Bow shocks are produced in the local interstellar medium by the passage of fast stars from the Galactic thin-disk and thick-disk populations with velocities V _* = 40–80 km s ^−1 . Stellar transits of local H i clouds occur every 3500–7000 yr on average and last between 10 ^4 and 10 ^5 yr. There could be 10–20 active bow shocks around low-mass stars inside clouds within 15 pc of the Sun. At local cloud distances of 3–10 pc, their turbulent wakes have transverse radial extents R _wake ≈ 100–300 au, angular sizes 10″–100″, and Ly α surface brightnesses of 2–8 R in gas with total hydrogen density n _H ≈ 0.1 cm ^−3 and V _* = 40–80 km s ^−1 . These transit wakes may cover an area fraction f _A ≈ ( R _wake / R _cl ) ≈ 10 ^−3 of local H i clouds and be detectable in IR (dust), UV (Ly α , two-photon), or nonthermal radio emission. Turbulent heating in these wakes could produce the observed elevated rotational populations of H _2 ( J ≥ 2) and influence the endothermic formation of CH ^+ in diffuse interstellar gas at T > 10 ^3 K.