In this chapter Marilina Cesario addresses the subject of weather forecasting in the Middle Ages as revealed in the meteorological prognostics that survive abundantly from throughout the period but particularly from the eleventh century onwards. The chapter focuses in particular on one fifteenth-century medical manuscript from Germany containing an anthology of seven Latin weather texts. Cesario edits and translates the texts for the first time and offers detailed discussion of them. She finds that these treatises contribute to their manuscript’s overarching interest in natural philosophy and that they were mostly given theoretical rather than practical usage, having their place in a context of academic learning (eruditio). One item stands out from the others, however, a puzzling salt prognostication found uniquely here. This text relies not, it is argued, on erudite knowledge but on knowledge acquired empirically and appears to have been designed for practical use.