Westlock lies on the Alberta plain, one of the Great Plains. It lies just to the north of the continental divide between the Athabasca and North Saskatchewan river basins, and to the east of the Pembina River, a tributary of the Athabasca. The town is about above mean sea level. Westlock sits within the humid continental climate zone, on the northern edge of the aspen parkland belt, a once heavily treed region that was cleared for agriculture at the turn of the 20th century. It is a relatively fertile region of dark soils. To the north lies the subarctic climate zone. The mean annual precipitation averaged from one meteorological station within the county measured 468 millimetres (mm), based on data from 1980 to 1990. The mean annual temperature averaged 1.9 °C, with the