Although it is well known that interaction with a mobile device can be impacted when the environment is inhospitable or when the user is on the move, situationally-induced impairments and disabilities (SIIDs) are often overlooked in the mobile interface design process. In this paper, we describe one step toward supporting mobile users with SIIDs, through the design of tactile notifications. The tactile channel offers considerable promise to convey notifications to the user, freeing their visual and auditory channels for other tasks. A study was conducted to determine whether participants could develop tactile cues to convey the key characteristics of alerts to mobile users (e.g. urgency, relationship with the sender). The results highlight the benefits of tactile prototyping tools to encourage generation of design ideas, and the use of scenarios to situate these design ideas within the intended context of use.