This chapter outlines the meteorological understanding of thunder in early modern England. In the Meteorologica, Aristotle explains atmospheric phenomena in a way which is recognisable to any reader of similar texts from Elizabethan and Jacobean England: a system of 'exhalations' and 'vapours', which are together best understood as 'evaporations'. Although meteorological theory in early modern England was based on the principles outlined by Aristotle, it was more specifically derived from the Roman thinkers who translated the texts from the Greek. Meteorological phenomena are generally explained as natural processes, with two exceptions. Either God interferes directly or some dark supernatural power subverts the natural order. There are examples of both of these exceptions in Shakespeare's plays. Thunder might be the result of an exhalation trapped in a cloud, but that same thunder could equally be interpreted as the voice of God or the work of a witch, depending on the interpreter.