We present in this paper a study of the conceptualisation of meteorological events involving water in Chinese based on Hantology, a SUMO-based ontology of Chinese orthography. Our comprehensive investigation of the morphosemantic behaviours of these weather words in both Mandarin and Sinitic languages reveals that they are predicted by the directionality and momentum of their formation and movement. We studied events involving water in both liquid and solid forms: such as rain, snow, hail, fog, dew and frost. They share the radical 雨, which can be linked to two SUMO nodes according to Hantology. This ontological bifurcation can be shown to bring about not only the diversity of direction expressions referring to these words for water, but also the differences of semantic features and PoS between them in Archaic Chinese. Moreover, the momentum of different water forms is proposed to be the physical basis for the differences of PoS, semantic features and node linking.