SYDNEY, Sept 16 (Reuters) - Large parts of Australia were in the grips of "uncommon" spring heat on Saturday, the nation's weather forecaster said, forecasting that record temperatures could be set on Sunday. The heat burst came after the forecaster said this week that indicators of an El Nino weather event had strengthened and it would likely develop between September and November, bringing hotter, drier conditions to Australia. The weather bureau said the "early period of heat" in many parts of the country was "very uncommon during September". "Record September daytime and nighttime temperatures are expected from Sunday through Thursday across inland areas of South Australia, New South Wales and northeast Victoria." Another local, Danielle Vangou, was worried about runners in the Sydney marathon, set to take place on Sunday.

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Persons: El Nino, Bella Callaghan, Danielle Vangou, Sam McKeith, Cordelia Hsu, Tom Hogue Organizations: New, Kingsford Smith Airport, Meteorology, Facebook, Sydney, Thomson Locations: Australia, Sydney, Australia's, New South Wales, El Nino, South Australia, Victoria, Bondi, Turkey