These datafiles contain observations collected with the Atmospheric Composition and Environmental Survey (ACES) platform during a series of mobile surveys in the metropolitan area of Montreal in October 2023. Each file contains calibrated data from a LI-COR LI-7810 and from an Airmar 220-WX weather station. The LI-COR LI-7810 measures atmospheric CH4, CO2 and H2O mole fractions and the Airmar 220-WX measures weather conditions (air temperature, atmospheric pressure, wind conditions) and GPS coordinates.