High resolution observations of interstellar Na I absorptions in the spectra of early-type stars in the second Galactic quadrant have been used to derive the spatial distribution of the nearby interstellar gas in the Galactic anticentre hemisphere. The data show the presence, within the region explored and within the nearest 150 pc, of eight diffuse interstellar clouds with LSR velocities in the range 15-55 km s^-1. Molecular gas previously identified close to the Sun by Trapero et al. (1995) and Trapero et al. (1996) is embedded in one of the clouds. The motion of these clouds does not reflect any motion of the gas away from the Scorpio-Centaurus association, showing that the kinematics observed in the neighbourhood of the Sun by Lallement and Bertin (1992) is restricted, in the second Galactic quadrant, to the nearest ~ 50 pc.