According to the records the coldest day was:

2018/08/09 07:00       -6.526 °C

and the hottest:

2018/12/17 13:00        37.616 °C

Ganora Temperatures

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South African Environmental Observation Network (SAEON) is a comprehensive, sustained, coordinated and responsive South African environmental observation network that delivers long-term reliable data for scientific research and informs decision-making; for a knowledge society and improved quality of life.