<p>Exploring the framing in the Chinese government's disaster science communication, as well as whether there are differences in framing between routine and emergency periods of a disaster, can help summarize the models of government-led science communication for disaster risk reduction. This study takes the content related to science communication on rainstorm disasters from the Chinese government’s 82 official Weibo accounts as the research object, and utilizes LDA topic modeling and sentiment lexicon matching to explore the three-tiered framing under both routine and emergency periods. The high-level framing explores the communication themes. Six themes were discovered, corresponding to three types of scientific knowledge: practical, theoretical, and conceptual. The mid-level framing examines the content preferences of the government in routine and emergency periods. It was found that the routine period focuses more on communicating theoretical and conceptual scientific knowledge, while the emergency period places more emphasis on the communication of practical scientific knowledge. The low-level framing explores the government’s emotional expression strategies in routine and emergency periods it was observed that in the routine period, encouraging and guiding expressions account for a higher proportion, while in the emergency period, conciliatory, mandatory, and emphasis expressions account for a higher proportion. These findings can serve as an effective complement to the scientific communication for disaster risk reduction efforts carried out by scientists.</p>