Heat-related mortality is of growing concern during heat-waves, particularly for the Montreal region. And the Urban Heat Island (UHI) effect is known to raise nocturnal urban temperatures when compared to rural surroundings. However, there are no good measurements of intra-city variability of temperatures available, as the data collected by Environment and Climate Change Canada (ECCC) is very sparse. Citizen Weather Stations (CWS) are an alternate source of Crowdsourced Geographic Information for urban climate research, which can provide extensive datasets in areas where data are scarce or unavailable. In this presentation, we explore the effectiveness of using meteorological data from Netatmo, a CWS, in studying the UHI effect in Montreal for late spring and summer of 2022. In particular, we evaluate the effectiveness of CWS for UHI Intensity estimates, and highlight the factors that affect their measurements. We also highlight that the resulting intensity values measured using CWS were higher than those estimated using either the Netatmo or the ECCC sensors individually, thus emphasizing the influence of sensor representativeness in estimating UHI magnitude. We also demonstrate the effectiveness of CWS sensors in delineating the specific areas of the city experiencing higher nocturnal temperatures on days conducive to the formation of UHI, and outline potential future avenues for the use of this data.