Sydney in 2015: A wet autumn, chilly winter, and hot spring

Sydney experienced its equal third-warmest year on record during 2015. Rainfall was close to average, with a severe East Coast Low in April resulting in the wettest single month since June 2007.

  • Equal third-warmest year for average mean temperatures
  • Fifth-warmest year for average maximum temperatures
  • Equal sixth-warmest year for average minimum temperatures
  • Close to average rainfall
  • Most severe East Coast Low since June 2007
  • Cold July including snow in the Blue Mountains
  • Record warmth in October and November
  • Tornado broke NSW wind gust record in December

The mean temperature in Sydney during 2015 was 19.1 °C, just behind the record warm years of 2013 (19.4 °C) and 2014 (19.3 °C). Minimum temperatures were well above average across the city, with nights 1.2 °C above average at Observatory Hill, the equal sixth-warmest year on record. Nights were warmer than average in most months, associated with very warm local sea surface temperatures during the year; 64 nights exceeded 20 °C, the equal second-highest number on record (average 27 nights). The exception was during July, which was the coolest for minimum temperatures in Sydney since 2002. Two cold outbreaks during the month contributed to the longest spell of nights below 8 °C since 1989, with snowfalls of up to 20 cm in the Blue Mountains.

Maximum temperatures were 1.5 °C above average at Observatory Hill, the fifth-warmest year on record, but closer to average elsewhere in the city. Temperatures reached at least 35 °C on seven days, the highest number since 2004 (average two days), with several notable heatwaves during spring. This included a temperature of 40.9 °C at Observatory Hill on 20 November, the second-warmest spring day on record.

Sydney Observatory Hill recorded 1337.2 mm of rainfall during 2015, slightly above the historical average, with average to above average rainfall across the city. The rain fell over 166 days, above the historical average of 144 rain days, with five days recording at least 50 mm (average four days). A severe East Coast Low caused a 48-hour total of 225.2 mm to 9 am on 22 April and substantial flooding. Wind gusts of up to 135 km/h and wave heights of 14.9 m were recorded during the event, as well as a record 44 consecutive hours with wind speeds greater than 50 km/h at Sydney Airport. This was the most severe East Coast Low since the "Pasha Bulker" storm of June 2007, with April consequently the wettest single month for Sydney since June 2007. At 30 December, Sydney's total water storage was at 93.1% of capacity, higher than at the end of 2014 (85.4%).

Notable events in 2015

This is a brief list of major weather events; for more information see the appropriate Monthly Climate Summaries.

  • Heavy rain on 26-27 January caused flash flooding in the city and along the Parramatta River.
  • Severe thunderstorms caused strong winds and roof damage in western Sydney on 11-12 March, large amounts of hail on 25 April, hail and flash flooding on 24 August, and two lightning-related injuries on 20 October.
  • A severe East Coast Low on 20-22 April produced very heavy rain, large waves, cool days and almost 48 hours of consecutive strong winds. This caused downed trees, widespread power outages, and coastal erosion.
  • Two cold outbreaks during July caused the longest spell of nights below 8 °C since 1989, as well as snow in the Blue Mountains on the 12th and 17th.
  • Heavy rainfall to the southeast of the city caused the Warragamba dam to spill on 26 August, leading to minor flooding in the Hawkesbury-Nepean River.
  • Spring heatwaves broke several early season records for warm temperatures, including three days above 32 °C on 4-6 October, 19 nights of 15 °C or higher on 4-22 October, and a maximum temperature of 40.9 °C on 20 November.
  • Severe thunderstorms across the city on 16 December produced heavy rain, large hail, flash flooding and strong winds. A wind gust of 213 km/h was reported from a category F2 tornado which damaged several houses and the desalination plant in Kurnell. This was the strongest wind gust ever recorded in New South Wales.

Further information

Media
(03) 9669 4057
Enquiries

Extremes in 2015
Hottest day 42.8 °C at Sydney Airport AMO on 20 Nov
Warmest days on average 24.3 °C at Penrith Lakes AWS
Coolest days on average 21.7 °C at Terrey Hills AWS
Coldest day 10.2 °C at Campbelltown (Mount Annan) on 16 Jul
Coldest night -2.6 °C at Camden Airport AWS on 6 Jul
Coolest nights on average 10.5 °C at Camden Airport AWS
Warmest nights on average 15.0 °C at Sydney (Observatory Hill)
Warmest night 24.3 °C at Parramatta North (Masons Drive) on 21 Dec
Warmest on average overall 19.2 °C at Sydney Airport AMO
Coolest on average overall 17.1 °C at Camden Airport AWS
Wettest overall 1586.0 mm at Frenchs Forest (Frenchs Forest Rd)
Driest overall 784.0 mm at Milperra Bridge (Georges River)
Wettest day 180.0 mm at Duffys Forest (Namba Rd) on 21 Apr
Strongest wind gust 213 km/h at Kurnell AWS on 16 Dec

Record highest daily rainfall
New record
(mm)
Old
record
Years of
record
Richmond RAAF 113.4 on 21 Apr 112.8 on 12 Feb 1997 22

Highest annual total rainfall for at least 20 years
Observed
(mm)
Most recent
higher
Annual
average
Prospect Reservoir 1139.0 1388.9 in 1990* 874.0

* note: there are gaps in the historical record at this site, so it is possible a higher value has gone unreported.


Summary statistics for 2015
Maximum temperatures
(°C)
Minimum temperatures
(°C)
Rainfall
(millimetres)
Mean
for
2015
Diff
from
average
Highest
for
2015
Mean
for
2015
Diff
from
average
Lowest
for
2015
Total
for
2015
Average
annual
total
Rank
of
2015
Fraction
of annual
average
Badgerys Creek AWS 23.7 -0.1 41.8 20 Dec 11.4 +0.7 -1.3 6 Jul 819.6 684.0 average 120%
Bankstown Airport AWS 23.9 +0.7 40.7 20 Nov 12.5 +0.5 0.6 4 Jul 931.2 874.6 average 106%
Camden Airport AWS 23.8 +0.1 40.9 20 Dec 10.5 +0.3 -2.6 6 Jul 813.6 788.8 average 103%
Campbelltown (Mount Annan) 23.6   40.4 20 Nov 10.8   -1.6 4 Jul 788.4
Canterbury Racecourse AWS 22.7 -0.3 40.6 20 Nov 12.1 -0.2 0.2 15 Jul
Holsworthy Aerodrome AWS 23.4   41.5 20 Nov 12.0   -0.5 4 Jul 823.4
Horsley Park Equestrian Centre AWS 23.5 -0.2 40.0 20 Dec 12.1 +0.1 -0.2 5 Aug 966.8 762.3 high 127%
Parramatta North (Masons Drive) 23.5 +0.2 41.0 20 Nov 12.6 +0.4 1.8 4 Jul 1132.5 970.6 high 117%
Penrith Lakes AWS 24.3 -0.3 41.9 20 Nov 12.7 +0.4 0.0 5 Aug 979.0 728.1 v high 134%
Prospect Reservoir 23.9 +0.7 40.4 20 Dec 12.6 +0.3 1.3 4 Jul 1139.0 874.0 high 130%
Richmond RAAF 24.1 0.0 39.7 20 Dec 11.6 +0.6 -2.5 6 Jul 1017.8 737.2 v high 138%
Sydney (Observatory Hill) 23.2 +1.5 40.9 20 Nov 15.0 +1.2 5.0 5 Aug 1337.2 1214.6 average 110%
Sydney Airport AMO 23.4 +1.1 42.8 20 Nov 14.9 +1.5 5.0 4 Jul
Terrey Hills AWS 21.7 -0.1 39.5 20 Nov 13.2 0.0 1.5 5 Aug 1183.6

Notes

The Annual climate summary lists 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.

A climate summary is generally published on the first working day of each month.

This statement has been prepared based on information available at 8 am on Wednesday 6 January 2016. 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

Climate

Service notice

Network problems on 8 January disrupted processing of observations, affecting some climate information. Missing data are being retrieved and will be processed into our systems over coming weeks.