The Continental Divide separates the state into two distinct climatic regions: the west generally has a milder climate than the east, where winters can be especially harsh. Montana's maximum daytime temperature averages 27°F (–2°C) in January and 85°F (29°C) in July. Great Falls has a normal daily mean temperature of 45°F (7°C), ranging from 21°F (–6°C) in January to 69°F (21°C) in July. The all-time low temperature in the state, –70°F (–57°C), registered at Rogers Pass on 20 January 1954, is the lowest ever recorded in the conterminous US; the all-time high, 117°F (47°C), was set at Medicine Lake on 5 July 1937. During the winter, Chinook winds from the eastern Rocky Mountains can bring rapid temperature increases of 40–50°F within a few minutes. Great Falls received an average annual precipitation (1971–2000) of 14.9 in (37.8 cm), but much of north-central Montana is arid. About 58.5 in (148.6 cm) of snow descends on Great Falls each year.