Monday, 2 December 2013 - Seasonal Climate Summary for Sydney - Product code IDCKGC25L0
Sydney Observatory Hill recorded 266.6 mm of rain during spring, slightly above the historical average of 229.3 mm. Most of the rain fell during November, which was the wettest for Sydney since 1984, while the September-October total was half the historical average. The rain fell over 24 rain days, well below the historical average of 34 days and the fewest since 2002, but nine days recorded at least 10 mm (average 6 days) and four recorded at least 25 mm (average 2 days).
Most of the rain during the season was associated with complex surface troughs and low pressure systems, with thunderstorm activity generating heavier local falls. Across the Sydney basin, heavy daily totals included:
Sydney Observatory Hill recorded an average maximum temperature of 24.7 °C during spring, 2.8 °C above the historical average and the warmest spring on record. Temperatures were warmest during the first part of the season, with the warmest September on record followed by the second-warmest October, associated with sunny conditions, westerly winds, and several very hot days. In contrast, above average rainfall resulted in closer to normal temperatures during November, which was the coldest month of the season.
Only seven days during the season failed to reach at least 20 °C (average 31 days), well below the previous record of 11 cool days in 2002 and 1988. There were ten days of at least 30 °C (average 4 days) and seven days above 32 °C (average 2-3 days); these included the second-earliest 31 °C day on record (7 September) and the third-warmest October day (37.3 °C on the 10th)
The average minimum temperature was 15.1 °C, 1.7 °C above the historical average and the equal-third-warmest on record. Nights were warm throughout the season, but particularly during September, which was the warmest on record for mean minimum temperatures as well as breaking the record for 9am temperatures on two occasions during the month.
The mean temperature for Sydney Observatory Hill was consequently 19.9 °C, 2.2 °C above the historical average and the warmest spring on record, 0.3 °C higher than the previous record in spring 1988. Notably, this follows the warmest winter on record for Sydney, recorded earlier this year.
Some sites had their highest spring mean daily maximum temperature on record.
The prevailing winds were variable during the season; September and October were dominated by anomalously northerly-westerly winds, contributing to warm, dry conditions, before a shift to cooler southerlies and easterlies during November. Strong winds caused damage on several occasions during September, with a tornado causing substantial damage in Hornsby during November.
The hot, dry, windy conditions contributed to substantial early-season bushfire activity during September and October. Notably, in the Springwood/Winmalee area of the Blue Mountains, two homes were destroyed during bushfires on 10 September, before a period of sustained bushfire activity between 17-23 October destroyed an additional 193 houses, as well as power, rail, and tourism infrastructure.
|Extremes in spring 2013|
39.3 °C at Penrith Lakes AWS on 8 Nov|
|Warmest days on average||
27.4 °C at Penrith Lakes AWS|
27.4 °C at Richmond RAAF
|Coolest days on average||
23.8 °C at Terrey Hills AWS|
15.0 °C at Springwood (Valley Heights) on 17 Nov|
2.7 °C at Camden Airport AWS on 15 Oct|
|Coolest nights on average||
9.6 °C at Camden Airport AWS|
|Warmest nights on average||
15.1 °C at Sydney (Observatory Hill)|
22.5 °C at Parramatta North (Masons Drive) on 9 Nov|
|Warmest on average overall||
20.1 °C at Sydney Airport AMO|
|Coolest on average overall||
17.9 °C at Campbelltown (Mount Annan)|
387.0 mm at Avalon (Wollstonecraft Ave)|
96.0 mm at Avalon (Wollstonecraft Ave) on 16 Nov|
|Highest wind gust||
100 km/h at Port Botany (Molineux Point AWS) on 10 Oct|
|Record highest spring mean daily maximum temperature|
Mean daily maximum
for spring 2013 (°C)
|Sydney (Observatory Hill)||24.7||24.2||in 2002||154||21.9|
|Sydney Airport AMO||25.3||24.5||in 2002||74||22.4|
|Prospect Reservoir||26.5||26.4||in 2002||46||23.5|
|Bankstown Airport AWS||26.2||26.0||in 2002||45||23.5|
|Summary statistics for spring 2013|
|Badgerys Creek AWS||26.3||38.1||8 Nov||10.6||4.1||12 Sep||198.0|
|Bankstown Airport AWS||26.2||+2.7||38.4||8 Nov||11.9||+0.3||5.6||15 Oct||211.4||183.6||average||115%|
|Camden Airport AWS||26.5||+2.5||38.3||8 Nov||9.6||-0.3||2.7||15 Oct||192.0||182.3||average||105%|
|Campbelltown (Mount Annan)||26.0||37.1||8 Nov||9.9||3.0||15 Oct||187.0|
|Canterbury Racecourse AWS||24.9||35.9||10 Oct||12.1||5.7||25 Oct||226.0|
|Holsworthy Aerodrome AWS||25.8||38.1||8 Nov||11.5||4.8||15 Oct||192.4|
|Holsworthy Control Range||25.8||38.3||8 Nov||10.8||3.6||25 Oct||169.0|
|Horsley Park Equestrian Centre AWS||26.2||37.9||8 Nov||11.9||5.1||15 Oct||175.2|
|Parramatta North (Masons Drive)||25.9||+2.3||38.2||8 Nov||12.5||+0.7||6.3||15 Oct||206.2||208.1||average||99%|
|Penrith Lakes AWS||27.4||39.3||8 Nov||12.0||5.7||27 Sep||167.0|
|Prospect Reservoir||26.5||+3.0||36.8||10 Oct||12.3||+0.4||5.7||15 Oct||209.7||179.8||average||117%|
|Richmond RAAF||27.4||38.8||8 Nov||10.8||3.4||25 Oct||100.2||181.7||low||55%|
|Springwood (Valley Heights)||25.1||36.8||8 Nov||11.8||6.0||15 Oct||219.6||226.9||average||97%|
|Sydney (Observatory Hill)||24.7||+2.8||37.3||10 Oct||15.1||+1.7||9.7||4 Oct||270.8||229.6||average||118%|
|Sydney Airport AMO||25.3||+2.9||37.8||10 Oct||14.9||+1.9||9.4||13 Sep||266.6||212.8||high||125%|
|Terrey Hills AWS||23.8||35.2||10 Oct||13.2||7.4||15 Oct||331.2|
A Seasonal Climate Summary is prepared to list the main features of the weather in 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 8 am on Monday 2 December 2013. Some checks have been made on the data, but it is possible that results will change as new information becomes available.
Averages are long-term means 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, as they cannot then be calculated reliably.
The median is sometimes more representative than the mean of long-term average rain.
The Rank indicates how rainfall this time compares with the climate record for the site,
based on the
(very low rainfall is in decile 1, low in decile 2 or 3,
average in decile 4 to 7, high in decile 8 or 9
and very high is in decile 10).
The Fraction of average shows how much rain has fallen this time as a percentage of the long-term mean.
The ACORN-SAT dataset is being used for temperature area averages from December 2012 onwards. The major change from earlier datasets is that the ACORN-SAT dataset commences in 1910, rather than 1950, and hence rankings are calculated using a larger set of years.