Temperature. The average annual temperature for temperate rainforests is about 0°C (32°F) because temperate rainforests are usually located close to the ocean, but for the warmer parts of the temperate rainforests the average annual temperature is around 20°C (68°F).emperature. The average annual temperature for temperate rainforests is about 0°C (32°F) because temperate rainforests are usually located close to the ocean, but for the warmer parts of the temperate rainforests the average annual temperature is around 20°C (68°F).