In this paper, we propose micro-climate sensing as an effective means of enhancing conventional RF-based localization. Our system targets people tracking applications in dynamic indoor environments, such as nursing homes, hospitals and office spaces that require simple deployment and where conventional RF tracking may suffer from timevarying signal attenuation or dropped packets. RF-based localization approaches suffer as the environment changes over time. To help mitagate these effects we use time synchronized windows of sensor samples to associate a mobile node with its nearby beacon nodes. In assisted living environments sensor networks likely already have basic sensors to collect contextual information about users and to monitor the environment. We propose using light, humidity, temperature and audio data samples over a short window of time to model the micro-climate of a beacon node. Using micro-climate matching in conjunction with RF signal strength decreases the worst-case loc...