Complex sentence: A week before the fires, an exceptional heatwave affected southeastern AustralMelbourne broke records by sweltering through three consecutive days above, with the temperature peaking at on 30 January, the third hottest day in the city's history.
Split into simpler sentences: A week before the fires, an exceptional heatwave affected southeastern Australia. From 28--30 January, Melbourne broke records by sweltering through three consecutive days above, with the temperature peaking at on 30 January, the third hottest day in the city's history.