Climate

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The Sydney Harbour Bridge in the 2009 Australian dust storm.

Sydney has a humid subtropical climate (Köppen climate classification: Cfa) with warm, sometimes hot summers and mild winters, with rainfall spread throughout the year.[1] The weather is moderated by proximity to the ocean, and more extreme temperatures are recorded in the inland western suburbs. The warmest months are January and February, with an average air temperature range at Observatory Hill of 18.7–25.9 °C (65.7–78.6 °F) for January and 18.8–25.8 °C (65.8–78.4 °F) for February.[2] An average of 14.9 days a year have temperatures of more than 30 °C (86 °F).[2]

In winter, temperatures rarely drop below 5 °C (41 °F) in coastal areas. The coldest month is July, with an average range of 8.0–16.3 °C (46.4–61.3 °F).[2] Rainfall is fairly evenly spread through the year, but is slightly higher during the first half of the year. The average annual rainfall, with moderate to low variability, is 1,213.8 mm (47.79 in), with rain falling on an average of 143.5 days a year.[2][3] Snowfall was last reported in the Sydney City area in 1836, while a fall of graupel, or soft hail, mistaken by many for snow, in July 2008, has raised the possibility that the 1836 event was not snow, either.[4][5] Extreme temperatures have ranged from 45.8 °C (114.4 °F) on 18 January 2013 to 2.1 °C (35.8 °F) on 22 June 1932, the lowest recorded minimum at Observatory Hill.[6][7] At the Sydney Airport station, extremes have ranged from 46.4 to −0.1 °C (115.5 to 31.8 °F).[8]

The city is rarely affected by cyclones, although remnants of ex-cyclones do affect the city. 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, 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 A$1.7 billion in less than five hours.[9]

The Bureau of Meteorology has reported that 2002 through 2005 were the warmest summers in Sydney since records began in 1859.[10] The summer of 2007–2008, however, proved to be one of the coolest summers on record.[11] Warmer and drier conditions came back in 2009 and 2010, when above-average temperatures were recorded. In 2009, the dry conditions brought a severe dust storm towards eastern Australia.[12][13] In 2011, above-average rainfall was recorded.[14]

On 18 January 2013, Sydney experienced record-breaking temperatures with 45.8 °C (114 °F) recorded at Observatory Hill.[15] The highest minimum temperature recorded at Observatory Hill is 27.6 °C (82 °F), in February 2011 while the lowest maximum temperature is 7.7 °C (46 °F), recorded in July 1868.[2]

The average annual temperature of the sea is above 20 °C (68 °F), and the monthly average ranges from 18 °C (64 °F) in July to 23 °C (73 °F) in January.[16][17]

Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year
Record high °C (°F) 45.8
(114.4)
42.1
(107.8)
39.8
(103.6)
35.4
(95.7)
30.0
(86.0)
26.9
(80.4)
26.5
(79.7)
31.3
(88.3)
34.6
(94.3)
38.2
(100.8)
41.8
(107.2)
42.2
(108.0)
45.8
(114.4)
Mean maximum °C (°F) 36.8
(98.2)
34.1
(93.4)
32.2
(90.0)
29.7
(85.5)
26.2
(79.2)
22.3
(72.1)
22.9
(73.2)
25.4
(77.7)
29.9
(85.8)
33.6
(92.5)
34.1
(93.4)
34.4
(93.9)
38.8
(101.8)
Mean daily maximum °C (°F) 27.0
(80.6)
26.8
(80.2)
25.7
(78.3)
23.6
(74.5)
20.9
(69.6)
18.3
(64.9)
17.9
(64.2)
19.3
(66.7)
21.6
(70.9)
23.2
(73.8)
24.2
(75.6)
25.7
(78.3)
22.8
(73.0)
Daily mean °C (°F) 23.5
(74.3)
23.4
(74.1)
22.1
(71.8)
19.5
(67.1)
16.6
(61.9)
14.2
(57.6)
13.4
(56.1)
14.5
(58.1)
17.0
(62.6)
18.9
(66.0)
20.4
(68.7)
22.1
(71.8)
18.8
(65.8)
Mean daily minimum °C (°F) 20.0
(68.0)
19.9
(67.8)
18.4
(65.1)
15.3
(59.5)
12.3
(54.1)
10.0
(50.0)
8.9
(48.0)
9.7
(49.5)
12.3
(54.1)
14.6
(58.3)
16.6
(61.9)
18.4
(65.1)
14.7
(58.5)
Mean minimum °C (°F) 16.1
(61.0)
16.1
(61.0)
14.2
(57.6)
11.0
(51.8)
8.3
(46.9)
6.5
(43.7)
5.7
(42.3)
6.1
(43.0)
8.0
(46.4)
9.8
(49.6)
12.0
(53.6)
13.9
(57.0)
5.3
(41.5)
Record low °C (°F) 10.6
(51.1)
9.6
(49.3)
9.3
(48.7)
7.0
(44.6)
4.4
(39.9)
2.1
(35.8)
2.2
(36.0)
2.7
(36.9)
4.9
(40.8)
5.7
(42.3)
7.7
(45.9)
9.1
(48.4)
2.1
(35.8)
Average rainfall mm (inches) 91.1
(3.59)
131.5
(5.18)
117.5
(4.63)
114.1
(4.49)
100.8
(3.97)
142.0
(5.59)
80.3
(3.16)
75.1
(2.96)
63.4
(2.50)
67.7
(2.67)
90.6
(3.57)
73.0
(2.87)
1,149.7
(45.26)
Average rainy days (≥ 1 mm) 8.2 9.0 10.1 7.9 7.9 9.3 7.2 5.6 5.8 7.6 8.7 7.9 95.2
Average afternoon relative humidity (%) 60 62 59 58 58 56 52 47 49 53 57 58 56
Average dew point °C (°F) 16.5
(61.7)
17.2
(63.0)
15.4
(59.7)
12.7
(54.9)
10.3
(50.5)
7.8
(46.0)
6.1
(43.0)
5.4
(41.7)
7.8
(46.0)
10.2
(50.4)
12.6
(54.7)
14.6
(58.3)
11.4
(52.5)
Mean monthly sunshine hours 232.5 205.9 210.8 213.0 204.6 171.0 207.7 248.0 243.0 244.9 222.0 235.6 2,639
Percent possible sunshine 53 54 55 63 63 57 66 72 67 61 55 55 60
Source 1: Bureau of Meteorology[18][19][20][21]
Source 2: Bureau of Meteorology, Sydney Airport (sunshine hours)[22]
  1. ^ "Climate and the Sydney 2000 Olympic Games". Australian Government. Australian Bureau of Statistics. 24 September 2007. Retrieved 21 December 2008.; "Sydney Basin – climate". New South Wales Government. Department of Environment and Climate Change. Retrieved 21 December 2008.; "Australian climatic zones". Australian Government. Bureau of Meteorology. Retrieved 21 December 2008.; "Living in Sydney". Sydney Institute of Business & Technology. Retrieved 21 December 2008.[dead link]
  2. ^ a b c d e "Climate statistics for Australian locations". Bureau of Meteorology. Retrieved 15 November 2013.
  3. ^ Australian Bureau of Meteorology. 2005. Ellyard, D. 1994. Droughts and Flooding Rains. Angus & Robertson ISBN 0-207-18557-3
  4. ^ "Sydney winter not snow, just hail". Mr Zmijewski doubted the 1836 snow report, saying weather observers of the era lacked the expertise of today. "We are almost in the sub-tropics in Sydney," he said. Sydney Morning Herald. Retrieved 15 November 2013.
  5. ^ MacDonnell, Freda. Thomas Nelson (Australia) Limited, 1967. Before King's Cross
  6. ^ "Sydney (Observatory Hill)". Climate statistics for Australian locations. Bureau of Meteorology. Retrieved 15 November 2013.
  7. ^ Bureau of Meteorology. 2006. Climate summary for Sydney, January 2006
  8. ^ "Sydney Airport AMO". Climate statistics for Australian locations. Bureau of Meteorology. Retrieved 13 December 2013.
  9. ^ "The Sydney Hailstorm – 14 April 1999". Bureau of Meteorology. Retrieved 5 October 2006.
  10. ^ Sydney has coldest June in 24 years in Sydney Monthly Climate Summary – NSW Regional Office, Bureau of Meteorology. Retrieved 21 October 2007.
  11. ^ "Sydney – Greater Sydney in 2008". Bom.gov.au. 5 January 2009. Retrieved 10 February 2012.
  12. ^ "Sydney in 2009". Bom.gov.au. 4 January 2010. Retrieved 10 February 2012.
  13. ^ "Sydney in 2010". Bom.gov.au. 4 January 2011. Retrieved 10 February 2012.
  14. ^ "Sydney in 2011". Bom.gov.au. 3 January 2012. Retrieved 10 February 2012.
  15. ^ Creagh, Sunanda. "Sydney smashes temperature records but heatwave nearly over". The Conversation. The Conversation Media Group. Retrieved 21 January 2013.
  16. ^ "Sydney Climate Guide". Retrieved February 2013. {{cite web}}: Check date values in: |accessdate= (help)
  17. ^ "Bondi Beach Water Temperature and Wetsuit Guide". This has been derived from analysis of two decades of oceanographic satellite measurements of nearby open water. Surf-Forecast.com. Retrieved 15 November 2013.
  18. ^ "Sydney (Observatory Hill) Period 1991-2020". Bureau of Meteorology. Retrieved 14 April 2020.
  19. ^ "Sydney (Observatory Hill): all years". Bureau of Meteorology. Retrieved 4 June 2018.
  20. ^ "Sydney (Observatory Hill): highest temperatures". Bureau of Meteorology. Archived from the original on Sep 27, 2023. Retrieved 23 September 2023.
  21. ^ "Sydney (Observatory Hill): lowest temperatures". Bureau of Meteorology. Retrieved 23 September 2023.
  22. ^ "Climate statistics for Australian locations Sydney Airport AMO". Bureau of Meteorology.