Keetmanshoop has a hot desert climate (Köppen climate classification "BWh"), with long, very hot summers and mild to warm winters. The annual average rainfall is only . Keetmanshoop is one of the sunniest places year-round on the planet with a mean sunshine duration over 3,870 h yearly or 10.7 sunny hours daily or well above 87% of the time. The annual mean temperature is 21.1 °C (70.0 °F) with a mean annual high of 28.8 °C (83.8 °F) and a low of 13.3 °C (55.9 °F). The climate is characterized by sunshine and dryness as well as moderate heat all year long.