Most of the fires started and spread on a day of some of the worst bushfire weather ever recorded. The temperature in Victoria reached 46 degrees Celsius and wind speed was more than 100 km/h. The wind blew the fires over large distances and areas, creating large firestorms. North-east of Melbourne, a single firestorm killed 120 people. A cool change hit the state in the early evening, but it had gale force south-westerly winds of more than 120 km/h. This change in wind direction caused the long eastern sides of the fires to become wide fire fronts that burned quickly towards towns that had earlier escaped the fires.