1. A person detection apparatus that detects a person from an input image captured by a capturing portion through pattern recognition using a recognition model to recognize a person, the apparatus comprising: a storage portion that stores a protector-hold recognition model describing a person who is using a protector against a specific weather and a no-protector recognition model describing a person who is using no protector; a weather determination section that determines a weather condition based on a detection result by a weather detection portion; and a person recognition section that performs pattern recognitions to the input image by using the protector-hold recognition model and the no-protector recognition model, which are stored in the storage portion, applies a ratio of an influence on the protector-hold recognition model and a ratio of an influence on the no-protector recognition model, in accordance with a determination result of a weather condition by the weather determination portion, and outputs, as a recognition result, a weather reflection score that is calculated by reflecting the ratio of the influence on the protector-hold recognition model and the ratio of the influence on the no-protector recognition model, respectively, in a result of performing the pattern recognition using the protector-hold recognition model and a result of performing the pattern recognition using the no-protector recognition model.