Sydney in autumn 2015: Wettest autumn since 2003

  • Wettest autumn since 2003
  • East Coast Low causes severe April weather
  • Warm nights across the city

Rainfall was well above average across the Sydney basin during autumn, which was the wettest for Observatory Hill since 2003. The rain fell over 38 days, of which 15 recorded at least 10 mm, above the autumn average of 10 wet days. The heaviest rainfall was associated with an east coast low in mid-April, with several stations breaking autumn daily rainfall records. Observatory Hill recorded 225.2 mm of rain in the 48 hours to 9am on the 22nd, the heaviest rainfall since 10-11 April 1998. This system also caused sustained strong winds, rough seas, and coastal erosion, resulting in flooding and power outages across the greater Sydney region.

Minimum temperatures were above average across the city during autumn, associated with generally warm sea surface temperatures and slightly below average sunshine hours. Nights were particularly warm in early May, with some stations recording their warmest May night on record on the 3rd. The mean maximum temperature was 1.2 °C above average at Observatory Hill, with very warm temperatures during March and five days above 30 °C, the highest frequency since autumn 2006 (average 2 days). However, days were very cold across the city between 20 to 22 April, with several locations recording their coldest April day in at least twenty years.

Further information

Media
(03) 9669 4057
Enquiries

Extremes in autumn 2015
Hottest day 37.9 °C at Sydney Airport AMO on 1 Mar
Warmest days on average 23.8 °C at Prospect Reservoir
Coolest days on average 21.7 °C at Springwood (Valley Heights)
21.7 °C at Terrey Hills AWS
Coldest day 12.6 °C at Springwood (Valley Heights) on 20 Apr
Coldest night 1.5 °C at Canterbury Racecourse AWS on 14 May
1.5 °C at Camden Airport AWS on 26 May
Coolest nights on average 11.3 °C at Camden Airport AWS
Warmest nights on average 15.4 °C at Sydney (Observatory Hill)
15.4 °C at Sydney Airport AMO
Warmest night 22.0 °C at Sydney (Observatory Hill) on 1 Mar
Warmest on average overall 19.4 °C at Sydney (Observatory Hill)
19.4 °C at Sydney Airport AMO
Coolest on average overall 17.1 °C at Canterbury Racecourse AWS
17.1 °C at Springwood (Valley Heights)
Wettest overall 625.0 mm at Frenchs Forest (Frenchs Forest Rd)
Driest overall 308.2 mm at Camden Airport AWS
Wettest day 180.0 mm at Duffys Forest (Namba Rd) on 21 Apr
Strongest wind gust 96 km/h at Sydney Airport AMO on 1 Mar
96 km/h at Sydney Airport AMO on 21 Apr

Record highest autumn daily rainfall
New record
(mm)
Old
record
Years of
record
Box Hill (Hynds Road) 113.0 on 21 Apr 110.8 on 19 May 1998 22
Richmond RAAF 113.4 on 21 Apr 77.0 on 19 May 1998 21
Badgerys Creek AWS 83.6 on 21 Apr 82.4 on 19 Apr 2012 20
Canterbury Racecourse AWS 123.0 on 21 Apr 100.0 on 11 Apr 1998 20
Penrith Lakes AWS 85.6 on 21 Apr 63.0 on 7 May 1996 20

Record highest autumn total rainfall
New record
(mm)
Old
record
Years of
record
Average for
autumn
Box Hill (Hynds Road) 453.0 382.0 in 2012 21 185.9
Richmond RAAF 441.6 286.2 in 1998 21 186.0
Penrith Lakes AWS 352.8 282.0 in 2003 20 165.3

Record lowest autumn temperature
New record
(°C)
Old
record
Years of
record
Average for
autumn
Canterbury Racecourse AWS 1.5 on 14 May 2.0 on 11 May 2011 20 12.8

Summary statistics for autumn 2015
Maximum temperatures
(°C)
Minimum temperatures
(°C)
Rainfall
(millimetres)
Mean for
autumn
2015
Diff
from
average
Highest for
autumn
2015
Mean for
autumn
2015
Diff
from
average
Lowest for
autumn
2015
Total for
autumn
2015
Average
for
autumn
Rank of
autumn
2015
Fraction of
autumn
average
Badgerys Creek AWS 23.0 -0.7 36.6 1 Mar 12.1 +0.8 4.3 10 May 361.8 175.7 v high 206%
Bankstown Airport AWS 23.6 +0.1 36.9 1 Mar 13.1 +0.3 3.1 14 May 395.6 255.1 high 155%
Camden Airport AWS 23.1 -0.6 34.2 1 Mar 11.3 +0.4 1.5 26 May 308.2 214.2 high 144%
Campbelltown (Mount Annan) 23.1   34.2 1 Mar 11.4   1.7 14 May 306.6
Canterbury Racecourse AWS 22.1 -1.2 35.9 1 Mar 12.1 -0.7 1.5 14 May 540.4 268.8 high 201%
Holsworthy Aerodrome AWS 23.0   35.5 1 Mar 12.5   4.1 14 May 314.0
Horsley Park Equestrian Centre AWS 23.2 -0.4 35.9 1 Mar 12.8 +0.2 4.1 14 May 401.2 204.9 v high 196%
Parramatta North (Masons Drive) 23.3 -0.2 36.2 1 Mar 12.9 0.0 4.7 14 May 528.5 273.4 v high 193%
Penrith Lakes AWS 23.7 -0.6 37.4 1 Mar 13.3 +0.3 3.9 14 May 352.8 165.3 highest 213%
Prospect Reservoir 23.8 +0.4 36.5 1 Mar 13.2 +0.2 5.4 26 May 423.0 243.7 high 174%
Richmond RAAF 23.6 -0.2 36.9 1 Mar 12.4 +0.9 2.0 14 May 441.6 186.0 highest 237%
Springwood (Valley Heights) 21.7   35.3 1 Mar 12.5   5.2 7 May 433.0 288.7 high 150%
Sydney (Observatory Hill) 23.4 +1.2 36.4 1 Mar 15.4 +0.8 7.9 14 May 541.8 377.8 high 143%
Sydney Airport AMO 23.3 +0.6 37.9 1 Mar 15.4 +1.2 7.3 14 May 482.2 323.2 high 149%
Terrey Hills AWS 21.7 -0.3 35.6 1 Mar 13.6 0.0 5.3 14 May 517.4

Notes

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.

A Climate Summary is generally published on the first working day of each month.

This statement has been prepared based on information available at 10 am on Monday 1 June 2015. Some checks have been made on the data, but it is possible that results will change as new information becomes available.

Averages for individual sites 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 10 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 decile ranking (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 used for temperature area averages.

Further information

Media
(03) 9669 4057
Enquiries