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Worldwide climate classifications

Sydney has a temperate climate with warm summers and cool winters, and rainfall spread throughout the year.^[1][2][3][4] The weather is moderated by proximity to the ocean, and more extreme temperatures are recorded in the inland western suburbs. The warmest month is January, with an average air temperature range at Observatory Hill of 18.6–25.8 °C (65–78 °F). There is an average of 14.6 days a year over 30 °C (86.0 °F). The maximum recorded temperature was 45.3 °C (113.5 °F) on 14 January 1939 at the end of a 4-day heat wave across Australia.^[5] The winter is mildly cool, with temperatures rarely dropping below 5 °C (41 °F) in coastal areas. The coldest month is July, with an average range of 8–16.2 °C (46–61 °F). The lowest recorded minimum at Observatory Hill was 2.1 °C (35.8 °F). Rainfall is fairly evenly divided between summer and winter, but is slightly higher during the first half of the year, when easterly winds dominate. The average annual rainfall, with moderate to low variability, is 1,217 mm (48 in), falling on an average 138 days a year.^[6] Snowfall was last reported in the Sydney City area in 1836.^[7] However, a July 2008 fall of graupel, or soft hail, mistaken by many for snow, has raised the possibility that the 1836 event was not snow, either.^[8]

The city is not affected by cyclones. The El Niño Southern Oscillation plays an important role in determining Sydney's weather patterns: drought and bushfire on the one hand, and storms and flooding on the other, associated with the opposite phases of the oscillation. Many areas of the city bordering bushland have experienced bushfires, notably in 1994 and 2001–02 — these tend to occur during the spring and summer. The city is also prone to severe hail storms and wind storms. One such storm was the 1999 hailstorm, which severely damaged Sydney's eastern and city suburbs. The storm produced massive hailstones of at least 9 cm (3.5 in) in diameter and resulting in insurance losses of around AUD $1.7 billion in less than five hours.^[9] The city is also prone to flash flooding from enormous amounts of rain caused by East Coast Lows (a low pressure depression which deepens off the state usually in winter and early spring which can bring significant damage by heavy rain, cyclonic winds and huge swells). The most notable event was the great Sydney flood which occurred on 6 August 1986 and dumped a record 327.6 mm (12.9 in) on the city in 24 hours. This caused major traffic problems and damage in many parts of the metropolitan area.^[10]

2009 Australian dust storm: On September 23, a dust storm that started in South Australia and inland New South Wales, Australia, blanketed New South Wales with reddish orange skies.^[11] It stretched as far north as southern Queensland.^[12]

See also

• Environment of Australia

References