A Temporal Information System, that incorporates temporal information into the traditional Information System of Rough Set Theory (RST) and Variable Precision Rough Sets (VPRS), is presented. Mobile Ad hoc Networks (MANETs) dynamically form a network without an existing infrastructure. The Dynamic Source Routing (DSR) protocol of MANETs is modified in this paper to use recent routes. Weighted elementary sets are introduced in temporal information systems and used to route packets in mobile ad hoc networks. Notions from VPRS are also brought into weighted temporal information systems and used in routing. The performance of these proposed routing protocols is studied.