Recently, there has been growing interest in the synthesis of conversational speech prosody. Conversational prosody is variable and carries many pragmatic functions. As speech synthesis research moves to using large amounts of untranscribed data, it is crucial that we understand the subtle pragmatic differences prosody can make. This study focuses on discourse markers, which are linguistic elements that perform various communicative functions, with their specific roles often linked to their prosodic realisation. In this paper, we explore the prosodic realisation of well using an unlabelled corpus of conversational speech. We use clustering to explore the variation in its prosodic realisation and identify common patterns in a data-driven manner. We synthesise the cluster centroids using controllable speech synthesis. Finally, we evaluate how the prosodic realisation of well affects the meaning of an utterance.