Temperature for January 1991
In January 1991 the average high temperature in Watertown, SD was 21.1°F, and this was 1.8°F cooler than the average of 22.9°F. The hottest day in January 1991 was 18 January when the temperature reached 39.9°F. Overnight the average temperature in January is 3.8°F and in 1991 the average overnight temperature was 1.3°F cooler at 2.6°F.