October's strong lead at 62.5% stems from heavy early rainfall, with Melbourne Olympic Park recording over 64 mm in the first nine days of 2026—including 48.4 mm on October 2, the city's wettest day in 30 months. This surge already matches or exceeds typical monthly averages for October (~64 mm) while September finished notably dry at under 20 mm. November (~62 mm average) and December (~50 mm) retain smaller shares due to their later timing and current lower cumulative totals, though late-spring patterns could still influence outcomes. Bureau of Meteorology observations confirm October's elevated totals to date, with additional showers possible before month-end.