Taroko National Park's climate is very much influenced by its terrain. Mountains taller than 2,000 m make up more than half of the 92,000 hectares of the Park grounds. The landscape ranges from a height of 60 m (low elevation) to 3,742 m (high elevation) at Nanhu's main peak.
In a year, the average temperature in Hualien is 23.7°C and drops as the elevation rises. Following the Central Cross-Island Highway, at an elevation of 1,000 m, the average temperature is 17.5°C; at 2,000 m the average temperature is 12.5°C; and at 3,000 m or above (e.g. Mt. Hehuan, Mt. Nanhu, the Qilai range); the average temperature is 7.7°C, and often below zero during January and February.
Average rainfall in the Park is around 2,000 mm per year, varying with terrain. During spring (March to May), spring rains fall in March and plum rains in May. During summer and autumn (June to August and September to November), typhoons are accompanied by rain. During winter (December to February), northeast monsoons bring rain as well. The Park's gorges often experience afternoon rain, and the amount increases with the elevation. At mid-elevation, there is more fog and high humidity.
Typhoons are one of Taiwan's water sources, but also often create changes to the environment. Most typhoons occur between July and September. Since the Park's terrain is high in the west and low in the east, the high mountains receive the full force of typhoons. Not only do they bring abundant rainfall, but typhoons also tend to cause rockfalls and landslides, damaging trails and roads in the Park.