Extreme weather events, such as typhoon and hurricane, have characteristics of high uncertainty, large destructiveness, and extensiveness, which threat the daily life and cause apparent perturbations to human mobility. In order to investigate the perturbation on human mobility, this study collects the metro transaction data before and during a typhoon weather event in Fuzhou, China, to conduct analyses. The ridership before and during the typhoon weather event is innovatively compared at system, station and origin-destination level. Besides, it is of novelty to examine the travel time distribution of metro trips in the normal and perturbed state by comparing three candidate models with the Akaike information criterion method. Results validate that the typhoon weather event severely influences the ridership at system, station, and origin-destination level, with various degrees. There is also significant impact on the relative total traveled stations from the typhoon weather event, especially for leisure trips. Moreover, the travel time of metro trips follows the gamma distribution in both the normal state and the perturbed state with different magnitudes. It is found that both the number of traveled stations and travel time are lower in the typhoon state when compared to those in the normal state. In general, this study can provide some helps to assist the metro management under extreme weather events.