Climate of Sydney

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During the 2009 Australian dust storm, the city of Sydney was shrouded in dust.
Main article: Climate of Australia

The climate of Sydney is temperate, having warm summers and cool winters, with rainfall spread throughout the year.[1][2][3][4]

Temperature[edit]

Smoke from bushfires around Sydney, January 1994

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.[5] An average of 14.9 days a year have temperatures of more than 30 °C (86 °F).[5] The highest recorded maximum temperature at Observatory Hill was 45.8 °C (114.4 °F) on 18 January 2013 during a prolonged heat wave across Australia from early December 2012 to late January 2013.[6][7] In winter, temperatures are mild and 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).[5] The lowest recorded minimum at Observatory Hill was 2.1 °C (35.8 °F) on 22 June 1932,[5] while the coldest in the Sydney metropolitan area was −5 °C (23 °F) at Liverpool.[8] Despite these temperature extremes, Sydney's overall climate is generally quite mild all year around; the city does not experience extreme seasonal weather differences. Summer days usually fall within the mid 20's and winter days in the mid teens.

Inland, in Sydney's western suburbs, the climate is drier and summers are significantly hotter with temperatures around 2–5 °C (4–9 °F) above Sydney's and winter lows around 2 °C (4 °F) cooler than the coastal suburbs.[9] Sydney is prone to heat waves, which have become considerably more common in recent years due to an increasing trend of global warming.[10] They usually would lead to water restrictions and a high risk of bushfires (that sometimes bring a smoky haze to the city).[11] Summer can vary between humid (due to the ocean proximity) or very dry (due to the heat from the desert).[12]

In late spring and summer, Sydney can sometimes get northwesterly winds from the Outback, which are dry and hot, making the temperatures soar above 35 °C (95 °F).[citation needed] This happens after the northwesterlies are carried entirely over the continental landmass, not picking up additional moisture from a body of water and retaining most of their heat. On these occasions, the normally temperate parts of south eastern Australia can experience the full fury of the desert climate, although only briefly, as they are often ended with a "southerly buster", which is a cold front that sweeps up from the southeast abruptly cooling the temperature by bringing thunderstorms and gale winds.[13][14][15]


Climate data for Sydney (Observatory Hill)
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)
33.9
(93)
30.0
(86)
26.9
(80.4)
25.9
(78.6)
31.3
(88.3)
34.6
(94.3)
38.2
(100.8)
41.8
(107.2)
42.2
(108)
45.8
(114.4)
Average high °C (°F) 25.9
(78.6)
25.8
(78.4)
24.7
(76.5)
22.4
(72.3)
19.4
(66.9)
16.9
(62.4)
16.3
(61.3)
17.8
(64)
20.0
(68)
22.1
(71.8)
23.6
(74.5)
25.2
(77.4)
21.7
(71.1)
Average low °C (°F) 18.7
(65.7)
18.8
(65.8)
17.6
(63.7)
14.7
(58.5)
11.5
(52.7)
9.3
(48.7)
8.0
(46.4)
9.0
(48.2)
11.1
(52)
13.6
(56.5)
15.6
(60.1)
17.5
(63.5)
13.8
(56.8)
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)
2.7
(36.9)
4.9
(40.8)
5.7
(42.3)
7.7
(45.9)
9.1
(48.4)
2.1
(35.8)
Rainfall mm (inches) 101.7
(4.004)
118.3
(4.657)
129.8
(5.11)
127.2
(5.008)
120.5
(4.744)
132.4
(5.213)
97.9
(3.854)
79.8
(3.142)
68.4
(2.693)
76.9
(3.028)
84.3
(3.319)
77.3
(3.043)
1,213.8
(47.787)
Avg. rainy days 12.2 12.5 13.5 12.8 13.1 12.5 11.2 10.4 10.5 11.6 11.7 11.5 143.5
 % humidity 62 64 62 59 57 57 51 49 51 56 58 57 56
Mean daily sunshine hours 7.1 6.7 6.4 6.4 5.9 5.5 6.4 7.1 7.2 7.2 7.8 7.6 6.8
Source #1: Bureau of Meteorology[5]
Source #2: [7]

Warm and cool periods[edit]

The Bureau of Meteorology has reported that 2002 through 2005 were the warmest summers in Sydney since records began in 1859. 2004 saw an average daily maximum temperature of 23.39 °C (74.10 °F), 2005 of 23.35 °C (74.03 °F), 2002 of 22.91 °C (73.24 °F), and 2003 of 22.65 °C (72.77 °F). The average daily maximum between 1859 and 2004 was 21.6 °C (70.9 °F). For the first nine months of 2006 the mean temperature was 18.41 °C (65.14 °F); the warmest year previously was 2004 with 18.51 °C (65.32 °F). Since November 2003, there have been only two months in which the average daily maximum was below average: March 2005 (about 1 °C (2 °F) below average)[20] and June 2006 (0.7 °C (1.3 °F) below average).[21]

The summer of 2007–08 proved to be one of the coolest on record. The Bureau of Meteorology reported that it was the coolest summer in 11 years, the wettest summer in six years, and one of only three summers in recorded history to lack a maximum temperature above 31 °C (88 °F).[22]

The Bureau of Meteorology reported that 2009 was a warm year, with above-average maximum temperatures. In 2009, the average annual daytime temperature at Observatory Hill was 22.9 °C (73.2 °F), which is 0.9 °C (1.6 °F) above the historical annual average. This ranks as seventh highest annual average maximum temperature since records commenced in 1859. It was the seventeenth consecutive year with above average annual maximum temperatures. Average night-time temperatures at Sydney Observatory Hill of 15.1 °C (59.2 °F) were well above (1.2 °C (2.2 °F)) the historical average during 2009. This is equal second highest in the 151 years of record, and the same as 1988.[23]

The year 2010 was a warm, wetter year with an average maximum of 22.6 °C (72.7 °F), which was 0.6 °C (1.1 °F) above the historical annual average. Night-time temperatures were also above average, at 15.0 °C (59.0 °F) during this year, compared to a historical average of 13.9 °C (57.0 °F). 2010 was the equal fourth warmest year on record for Sydney. Seven (of the ten) warmest years on 151 years of record have occurred in the ten years between 2001 and 2010, with this decade being the warmest on record for minimum temperatures.[24]

Towards the end of January 2011 the city had a heat wave that brought up the temperatures to over 30 °C (86 °F) for five consecutive days. The west had five days with temperatures over 35 °C (95 °F).[25] February 2011 was the second warmest on record for mean temperatures and third warmest for maxima.

In 2013, the city had the warmest July and September on record,[26][27] with September being one of the driest with the temperatures being 4 °C (7 °F) above average.[28] The city had over seven days with temperatures reaching 28 °C (82 °F), making it more similar to November's weather pattern.[29] October was also a warmer than average month where the temperature peaked at 37 °C (99 °F), making it the third hottest October day.[30] Sydney's summer of 2013-14 did not record any temperatures above 37 °C (99 °F) for the first time in two years, with January being cooler than the previous September and October.[31]

Precipitation[edit]

Rainfall is fairly evenly spread through the year, but is slightly higher during the first half of the year when easterly winds dominate (February–June), and lower in the second half (mainly July–September).[32][33] The average annual rainfall in the city at Observatory Hill, with moderate to low variability, is 1,213.8 mm (47.79 in), falling on an average 143.5 days a year.[5] As seen from the climate table above, Sydney's wettest month is June,[5][16] though most of its western suburbs' wettest month is February or March.[17][18][19] The driest months are July through to September.[5][16][17][18][19] Within the city and surrounds, rainfall varies, from around 682.5 mm (26.87 in) at Badgerys Creek (in the west) to 1,213.8 mm (47.79 in) at Observatory Hill (the east).[5][34]

Snowfall was last reported in the Sydney City area in 1836. T. A. Browne, who kept weather observations, noted that "the years 1836, 1837 and 1838 were years of drought, and in one of these years (1836) a remarkable thing happened. There was a fall of snow; we made snowballs at Enmore and enjoyed the usual schoolboy amusements therewith". The Sydney Herald reported on the same incident, saying, "for the first time in the memory of the oldest inhabitants, snow fell in Sydney on the morning of Tuesday last. 27 June 1836, about 7 O'clock in the morning, a drifting fall covered the streets nearly one inch in depth."[35] 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.[36]

Even in its months of highest rainfall Sydney has relatively few rainy days, on average less than 14 rainy days per month.[5][16][17][18][19] This means the average rain event in Sydney contains heavy rain. The city is not affected by cyclones, although remnants of ex-cyclones do affect the city.[37] 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.

The city is prone to severe hail storms, such as the 1947 Sydney hailstorm, wind storms, and flash flooding from rain caused either by East Coast Lows (during autumn-winter periods) and Ex-Tropical Cyclone remnants (during spring-summer periods). They are low pressure depressions that can bring significant damage by heavy rain, cyclonic winds and huge swells.

Notable events[edit]

A boat at Rose Bay during the 1947 Sydney hailstorm

A notable event was the great Sydney flood which occurred on 6 August 1986 (unusual in that month) and dumped a record 327.6 mm (12.90 in) on the city in 24 hours. This caused major traffic problems and damage in many parts of the metropolitan area.[38] The next notable event 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.[39]

In the first weeks of February 2010, Sydney received some of the highest rainfalls in 25 years, which caused flash flooding and traffic chaos. On 4 February, some suburbs in the North Shore region recorded their heaviest rain in 20 years. On 12 and 13 February, some suburbs were hit by thunderstorms which brought heavy rain and gusty winds which cut out power and damaged homes.[40][41] On 13 February, Sydney experienced one of the highest rainfall of the last decade with 65 mm (2.6 in) of rain falling in one night at Observatory Hill.[42] The heavy rain was caused by remnants of ex-tropical Cyclone Olga and humid north-easterly winds feeding into the low pressure trough.[43][44] 2010 was the wettest year since 2007, according to the Bureau of Meteorology, with the cloudiest October and the third cloudiest July on record.

March and April 2011 were very wet with well above average rainfall. March recorded 191.6 mm (7.54 in) well above the average of 128.9 mm (5.07 in) of rain and was the wettest March in ten years. April 2011 recorded 206.2 mm (8.12 in) of rain well above the average of 125.8 mm (4.95 in) and was the wettest April since 1999. May 2011 also recorded above average rainfall, making it the wettest autumn since 2003 according to the Bureau.[45][46] July 2011 was the wettest July since 1950.[47]

In November 2013, a tornado hit Hornsby, a suburb in the Upper North Shore. The tornado's path was 2 km long and 2m wide.[citation needed] The tornado blew off roofs, partially collapsed a cinema roof, and toppled large trees. The winds in the tornado reached 140 km an hour.[48][49]

Drought[edit]

Sydney is occasionally prone to drought[50][51] as Sydney's climate appears to be becoming drier. The city has had fewer rain days in recent years than shown in the long-term climate table above. The years 2009 and 2010 had dry conditions, according to Bureau of Meteorology.[52] In 2011, Sydney had the driest February in 30 years with only 18 mm (0.71 in) of rain falling, which is well below than the average 118 mm (4.6 in). Some of the western suburbs recorded the lowest total February rainfall on record.[53]

In September 2013, the combination of dry weather, warm temperatures and strong winds brought early-season bushfires. Major bushfires impacted western Sydney and the Blue Mountains, resulting in some evacuations, closed roads, and destroyed homes.[27]

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.

Dust storms[edit]

On 23 September 2009, a dust storm that started in South Australia and inland New South Wales blanketed the city with reddish orange skies.[54] It stretched as far north as southern Queensland and it was the worst dust storm in 70 years.[55] During that year, Sydney experienced a number of warm winter days, dry gusty winds and another milder dust storm.[56][57]

See also[edit]

References[edit]

  1. ^ "Climate and the Sydney 2000 Olympic Games". Australian Government. Australian Bureau of Statistics. 24 September 2007. Retrieved 21 December 2008. 
  2. ^ "Sydney Basin - climate". New South Wales Government. Department of Environment and Climate Change. Retrieved 21 December 2008. 
  3. ^ "Australian climatic zones". Australian Government. Bureau of Meteorology. Archived from the original on 5 July 2008. Retrieved 21 December 2008. 
  4. ^ "Living in Sydney". Sydney Institute of Business & Technology. Archived from the original on 8 August 2008. Retrieved 21 December 2008. 
  5. ^ a b c d e f g h i j "Sydney (Observatory Hill)". Climate statistics for Australian locations. Bureau of Meteorology. Retrieved 19 January 2014. 
  6. ^ "Special Climate Statement 43 – extreme heat in January 2013". Bureau of Meteorology. 1 February 2013. Retrieved 2 February 2013. 
  7. ^ a b c d e "Sydney in January 2013: An extreme month for Sydney". NSW Climate Services Centre. Bureau of Meteorology. 1 February 2013. Retrieved 2 February 2013. 
  8. ^ Template:Cite http://weather.ninemsn.com.au/climate/station.jsp?lt=site&lc=67035
  9. ^ Sydney’s Climate
  10. ^ "Sydney heatwave: Is it hot enough for you?". The Sydney Morning Herald. 10 October 2013. Retrieved 23 January 2014. 
  11. ^ The Best Time to Visit Sydney - Summer
  12. ^ "Sydney heatwave". Daily Liberal. 2013. Retrieved 4 February 2014. 
  13. ^ Sydney Weather
  14. ^ Southerly buster
  15. ^ Heatwave blows in on a fiery desert wind
  16. ^ a b c d "Sydney/Kingsford-Smith International Airport". Climate statistics for Australian locations. Bureau of Meteorology. Retrieved 19 January 2014. 
  17. ^ a b c d "Sydney Olympic Park". Climate statistics for Australian locations. Bureau of Meteorology. Retrieved 19 January 2014. 
  18. ^ a b c d "Liverpool". Climate statistics for Australian locations. Bureau of Meteorology. Retrieved 19 January 2014. 
  19. ^ a b c d "Penrith". Climate statistics for Australian locations. Bureau of Meteorology. Retrieved 19 January 2014. 
  20. ^ Cool, cloudy and rainy end to March in Sydney in Sydney Climate Summary — NSW Regional Office, Bureau of Meteorology. Retrieved 21 October 2007.
  21. ^ Sydney has coldest June in 24 years in Sydney Monthly Climate Summary — NSW Regional Office, Bureau of Meteorology. Retrieved 21 October 2007.
  22. ^ Sydney has coolest summer in 11 years in Sydney Climate Summary — NSW Regional Office, Bureau of Meteorology. Retrieved 25 March 2008.
  23. ^ Year 2009: Very warm with below average rainfall in Sydney
  24. ^ Sydney in 2010: 18th consecutive warm year
  25. ^ Special Climate Statement 27 - An exceptional summer heatwave in greater Sydney and the Hunter Valley.
  26. ^ Sydney in July 2013: Warmest July on record
  27. ^ a b Sydney in September 2013: Warmest September on record
  28. ^ Climate Council reports warmest September on record
  29. ^ September’s average temperature for Sydney beats 33-year-old record
  30. ^ Sydney gets its third hottest October day
  31. ^ "Historical Weather For The Last Twelve Months in Sydney, Australia". WeatherSpark. Retrieved 2 March 2014. 
  32. ^ Climate of Sydney Australia the Good and the Bad
  33. ^ Australia > New South Wales > Sydney
  34. ^ "Badgerys Creek AWS". Climate statistics for Australian locations. Bureau of Meteorology. Retrieved 19 January 2014. 
  35. ^ MacDonnell, Freda. Thomas Nelson (Australia) Limited, 1967. Before King's Cross
  36. ^ "Sydney weather hail, not snow". AAP. 27 July 2008. Archived from the original on 2009-01-06. Retrieved 2008-08-11. 
  37. ^ Tropical Cyclones in New South Wales
  38. ^ Rain in Sydney, 1986 in Australian Climate Extremes, Bureau of Meteorology. Retrieved 9 September 2006.
  39. ^ "The Sydney Hailstorm - 14 April 1999". Bureau of Meteorology. Retrieved 2006-10-05. 
  40. ^ "Storm drenches Sydney". UPI.com. 12 February 2010. Retrieved 2010-06-01. 
  41. ^ "Sydney dries out but regional threatened". News.smh.com.au. 12 February 2010. Retrieved 2010-06-01. 
  42. ^ "Weather News - Wild storms lash Sydney". Weatherzone.com.au. 13 February 2010. Retrieved 2010-06-01. 
  43. ^ "Rain swamps Sydney's water catchments". Smh.com.au. 7 February 2010. Retrieved 2010-06-01. 
  44. ^ Huffer, Julie (2010-02-10). "Heaviest rain in almost 20 years - Environment - News | Hornsby & Upper North Shore Advocate". Hornsby-advocate.whereilive.com.au. Archived from the original on 2013-01-20. Retrieved 2010-06-01. 
  45. ^ Sydney in April 2011: Wettest April since 1999
  46. ^ Sydney in May 2011: Coldest nights in 40 years
  47. ^ Sydney's wettest July since 1950
  48. ^ http://www.abc.net.au/news/2013-11-19/clean-up-continues-after-tornado-strikes-in-sydney27s-north/5101560
  49. ^ "Hornsby was hit by a tornado, Bureau of Meteorology confirms". The Sydney Morning Herald. 
  50. ^ "Water quality and drought". Sydney Water. Archived from the original on 2009-11-20. 
  51. ^ "Drought". Archived from the original on 2012-01-15. 
  52. ^ "Year 2009: Very warm with below average rainfall in Sydney". Bom.gov.au. 4 January 2010. Retrieved 2014-01-19. 
  53. ^ Sydney in January 2011: Warm start to 2011
  54. ^ Ramachandran, Arjun (23 September 2009). "Sydney turns red: dust storm blankets city". The Sydney Morning Herald. 
  55. ^ Brisbane on alert as dust storms sweep east
  56. ^ "Sydney in Autumn 2010". Bom.gov.au. Retrieved 2010-06-01. 
  57. ^ "Third warmest winter on record for Sydney". Bom.gov.au. 27 August 1995. Retrieved 2010-06-01. 

External links[edit]