Tuesday, 1 June 2010 - Seasonal Climate Summary for Sydney - Greater Sydney - Product code IDCKGC25L0
Warm and dry Autumn
- Below average rainfall.
- Above average temperatures (maximum and minimum).
Sydney Observatory Hill recorded 249.6 mm in autumn which is below the historical average1 of 397.1 mm. The below average rainfall was mainly a product of well below average falls which were recorded in both March and April, despite good falls in the second half of May. The rain during autumn fell on 35 rain days which is below the historical average1 of 37 rain days. The dry conditions were due to the passage of several high pressure systems which brought mostly fine weather to Sydney. Much of the rainfall that did fall during autumn was restricted to coastal areas, resulting in much drier conditions in western parts of Sydney.
Sydney's storage levels at the start of autumn were at 59.3% and dropped to 56.3% at the end of May as much of the rainfall that fell in the Sydney basin was restricted to coastal areas. Recent rainfall and current levels in Sydney's water catchments can be found on the Sydney Catchment Authority web site http://www.sca.nsw.gov.au/dams/rainfall.html
Warm conditions were recorded across the Sydney basin during autumn for both maximum and minimum temperatures. Sydney Observatory Hill recorded an average mean temperature (average of maximum and minimum temperatures) of 19.7°C which is 0.7°C above the historical average1 of 19.0°C. The passage of several high pressure systems throughout autumn brought mostly fine weather during the day resulting in above average maximum temperatures. Onshore winds and high humidity associated with the above average sea surface temperatures in Sydney contributed to the above average minimum temperatures. Very warm conditions persisted for the most part until the 17th of May with mostly cooler than normal conditions recorded for the remainder of autumn.
Sydney Observatory Hill recorded an average maximum temperature of 23.7°C which is 0.8°C above the historical average1 of 22.9°C. The warmest daily maximum temperature of 36.3°C was recorded at Sydney Airport on 21st March with the warmest average maximum temperatures for autumn of 24.8°C recorded at Penrith Lakes.
Sydney Observatory Hill recorded an average minimum temperature of 15.8°C which is 0.7°C above the historical average1 of 15.1°C. The warmest night of 23.0°C was recorded at Sydney Airport with the warmest nights on average recorded at Sydney Observatory Hill (15.8°C). The coldest night was -0.7°C recorded at both Richmond RAAF and Camden Airport AWS on 13th of May.
Prevailing winds in coastal Sydney during the afternoon (3pm) were between E and SE for 63% of the time during May (observations taken from Sydney Airport). The strongest wind gust of 81 km/hr was recorded at Sydney Airport on 21st March.
Sydney recorded a total of 2 storms during autumn which is below the the historical average1 of 6 storms. Sunshine averaged at 6.7 hours per day which is above the historical average1 of 6.3 hours. On the morning of the 21st of April fog was observed at many locations across greater Sydney.
|Extremes in autumn 2010|
36.3 °C at Sydney Airport AMO on 21 Mar|
|Warmest days on average||
24.8 °C at Penrith Lakes AWS|
|Coolest days on average||
22.3 °C at Terrey Hills AWS|
13.7 °C at Terrey Hills AWS on 18 May|
-0.7 °C at Camden Airport AWS on 13 May|
-0.7 °C at Richmond RAAF on 13 May
|Coolest nights on average||
10.8 °C at Camden Airport AWS|
|Warmest nights on average||
15.8 °C at Sydney (Observatory Hill)|
23.0 °C at Sydney Airport AMO on 29 Mar|
342.9 mm at Avalon Beach (Avalon (Palmgrove Rd))
98.0 mm at Ingleburn (Sackville Street) on 31 Mar|
|Highest wind gust||
81 km/h at Sydney Airport AMO on 21 Mar|
|Summary statistics for autumn 2010|
|Springwood Bowling Club||22.5||33.9||21 Mar||12.9||5.0||13 May||170.4||288.5||low||59%|
|Bankstown Airport AWS||24.1||+0.7||34.4||26 Mar||13.1||+0.3||4.3||13 May||200.2||251.3||average||80%|
|Canterbury Racecourse AWS||23.9||35.1||21 Mar||13.2||4.9||13 May||159.0|
|Holsworthy Control Range||24.3||35.8||21 Mar||12.2||3.6||6 May||119.0|
|Parramatta North (Masons Drive)||24.1||+0.6||35.2||21 Mar||13.1||+0.2||5.2||13 May||188.8||265.7||average||71%|
|Riverview Observatory||23.6||+1.1||34.5||21 Mar||13.7||+0.8||6.8||13 May||227.9||339.1||low||67%|
|Sydney (Observatory Hill)||23.7||+1.5||30.9||21 Mar||15.8||+1.2||9.0||13 May||249.6||375.8||average||66%|
|Sydney Airport AMO||23.8||+1.1||36.3||21 Mar||15.7||+1.5||7.9||13 May||244.8||320.1||average||76%|
|Sydney Olympic Park (Sydney Olympic Pk A||24.2||35.9||21 Mar||14.9||8.0||13 May||201.4|
|Terrey Hills AWS||22.3||33.0||26 Mar||14.1||6.1||13 May|
|Badgerys Creek AWS||24.4||35.1||26 Mar||11.3||2.0||13 May||132.2|
|Horsley Park Equestrian Centre AWS||24.2||34.9||21 Mar||12.8||3.6||13 May||112.0|
|Liverpool (Michael Wenden Centre)||24.7||35.5||21 Mar||12.0||1.6||27 Apr||175.6|
|Penrith Lakes AWS||24.8||36.0||21 Mar||13.0||3.5||13 May||95.4|
|Prospect Reservoir||24.5||+1.1||35.2||26 Mar||13.1||+0.1||4.1||13 May||175.7||241.7||average||73%|
|Richmond RAAF||24.2||35.1||21 Mar||11.5||-0.7||13 May||114.0|
|Camden Airport AWS||24.6||+0.9||35.2||21 Mar||10.8||-0.2||-0.7||13 May||161.8||208.0||average||78%|
|Campbelltown (Mount Annan)||24.7||35.2||21 Mar||11.3||1.0||13 May||134.0|
A Seasonal Climate Summary is prepared to list the main features of the weather in Sydney - Greater Sydney using the most timely and accurate information available on the date of publication; it will generally not be updated. Later information, including data that has had greater opportunity for quality control, will be presented in the Monthly Weather Review, usually published in the fourth week of the month.
This statement has been prepared based on information available at 10 am on Tuesday 1 June 2010. Some checks have been made on the data, but it is possible that results will change as new information becomes available.
A note about deciles: Deciles are used to give an element (in this case rainfall or temperature) a ranking. Deciles are calculated by arranging the totals in ascending order (from lowest to highest) then splitting them into 10 equal groups (thus the groups are called deciles). The first group would be in decile range one, the second group in decile range two, etc up to the highest annual totals (highest 10 per cent) being in decile range 10.
1Averages: Averages are based on the period 1961 to 1990 which is a convention of the World Meteorological Organisation
Normals are long-term averages based on observations from all available years of record, which vary widely from site to site. They are not shown for sites with less than 20 years of record for temperature and less than 30 years of record for rainfall, as they cannot then be calculated reliably.