Sydney in July 2011: Wettest July in 60 years in the eastern suburbs

  • Wettest July since 1950 in the city.
  • Wettest four-day period for any month since 1998 associated with an ECL event.
  • Above average temperatures in the city; cool days in the west.

Rainfall

Sydney Observatory Hill recorded 282.0 mm of rain during July, well above the historical average of 97.4 mm. This was the wettest July since 336.1 mm was recorded in July 1950, and the 7th wettest on record for the city. Rain was very heavy in the eastern suburbs, with totals reaching 319.5 mm at Castle Cove and 312.8 mm at Cronulla, including record-breaking totals at several stations. In comparison, western Sydney received average to below average rainfall during July, with just 26 mm at Penrith and 27.0 mm at Springwood, half the July average.

The high July rainfall was due solely to an East Coast Low event, which brought heavy rain to coastal Sydney between the 20th and 23rd but little rain in western regions. Daily falls reached 130 mm at Terry Hills and 129 mm at Castle Cove on the 22nd, including the wettest day in 65 years of record at Cronulla, while Observatory Hill recorded a 4-day total of 261.8 mm, the wettest four days since an ECL in August 1998 and the wettest for July since 1931.

Some sites had their highest total July rainfall on record.

Temperature

Sydney Observatory Hill recorded an average maximum temperature of 17.4 °C during July, 1.1 °C above the historical average. Temperatures were particularly warm at the end of the month, with four consecutive days above 20 °C between the 28th and 31st. In comparison, most other stations recorded below average temperatures, reaching -1.0 °C below average at Prospect Reservoir.

Minimum temperatures were above average across Sydney, 0.6 °C above the historical average of 8.0 °C at Observatory Hill and as high as 1.5 °C above average at Sydney Airport. The warm minimums were associated with a series of warm nights at the start of the month, with nine nights above 10 °C recorded during July compared to the historical average of 6 nights. However, temperatures reached a low of just 5.5 °C at Observatory Hill on the 8th, and -3.1 °C at Richmond on the 9th, associated with cold southerly winds and reports of snow in the Blue Mountains.

Wind

Sydney Airport was dominated by westerly to northwesterly winds during July, forming 67% of 9am winds and 50% of 3pm winds, with a further 40% of 3pm winds from a southerly to southwesterly direction. Eight strong wind days were reported at the Airport, well above the historical average of four days and the highest July frequency since 1999.

The strongest winds in the Metropolitan region were recorded during the ECL on the 20th, reaching 100 km/hr at Port Botany, associated with minor damage in the eastern suburbs. Very strong winds were also recorded in the Blue Mountains, reaching 139 km/hr at Mt Boyce on the 5th, its strongest gust since records began in 2003, as well as gusts above 90 km/hr on the 6th, 7th, 10th, and 11th. The strong winds during this period caused substantial damage in the Blue Mountains, particularly on the 7th and 8th, with numerous fallen trees causing damage to houses and trains and large areas without power.

Other phenomena

Sunshine averaged 6.6 hours at the Airport, equal to the historical average.. There were no thunderstorms at Sydney Airport during July and only one fog day, average for July.

Further information

Media
(03) 9669 4057
Enquiries

Extremes in July 2011
Hottest day 21.4 °C at Sydney (Observatory Hill) on the 31st
21.4 °C at Sydney Olympic Park (Sydney Olympic Pk A on the 31st
Warmest days on average 17.4 °C at Sydney (Observatory Hill)
Coolest days on average 15.3 °C at Terrey Hills AWS
Coldest day 9.5 °C at Richmond RAAF on the 13th
Coldest night -3.1 °C at Richmond RAAF on the 9th
Coolest nights on average 4.0 °C at Camden Airport AWS
4.0 °C at Richmond RAAF
Warmest nights on average 8.6 °C at Sydney (Observatory Hill)
8.6 °C at Sydney Airport AMO
Warmest night 12.2 °C at Sydney (Observatory Hill) on the 5th
Warmest on average overall 13.0 °C at Sydney (Observatory Hill)
Coolest on average overall 10.5 °C at Badgerys Creek AWS
10.5 °C at Camden Airport AWS
10.5 °C at Richmond RAAF
Wettest overall 319.5 mm at Castle Cove (Rosebridge Ave)
Wettest day 130.4 mm at Terrey Hills AWS on the 22nd
Highest wind gust 100 km/h at Port Botany (Molineux Point AWS) on the 20th


Record highest total July rainfall
Total rainfall
for July 2011 (mm)
Previous wettest
for July
Years of
record
Average for
July
Castle Cove (Rosebridge Ave) 319.5 195.1 in 1976 52 73.8
Mona Vale Golf Club 287.6 162.6 in 1984 42 70.1
Avalon Beach (Avalon (Palmgrove Rd)) 196.2 173.0 in 1997 33 75.5
Peakhurst Golf Club 164.0 158.6 in 1975 33 48.3



Summary statistics for July 2011
Maximum temperatures
for July
(°C)
Minimum temperatures
for July
(°C)
Rainfall
for July
(millimetres)
Mean for
July
2011
Diff
from
average
Highest for
July
2011
Mean for
July
2011
Diff
from
average
Lowest for
July
2011
Total for
July
2011
Average
for
July
Rank of
July
2011
Fraction of
July
average
Badgerys Creek AWS 16.8   20.6 4th 4.2   -1.7 12th 47.0
Bankstown Airport AWS 16.7 -0.5 20.1 4th 5.8 +0.7 0.6 8th 111.8 46.1 v high 243%
Camden Airport AWS 16.9 -0.3 20.4 29th 4.0 +1.0 -2.1 8th 46.4 39.2 average 118%
Campbelltown (Mount Annan) 16.9   21.3 4th 4.4   -2.0 8th 62.2
Canterbury Racecourse AWS 16.8   20.6 31st 6.1   0.9 8th 179.2
Holsworthy Control Range 16.6   20.4 4th 5.0   -1.8 8th 95.2
Horsley Park Equestrian Centre AWS 16.5   20.0 4th 5.5   0.1 8th 76.2
Liverpool (Michael Wenden Centre) 17.2   21.2 4th 4.2   -1.5 8th 72.1
Parramatta North (Masons Drive) 16.6 -0.7 20.2 30th 6.3 +0.1 1.0 9th 132.1 47.1 v high 280%
Penrith Lakes AWS 17.3   21.2 4th 5.5   -0.3 9th 27.2
Prospect Reservoir 15.8 -1.0 20.7 4th 6.1 0.0 0.8 8th 85.2 57.3 high 149%
Richmond RAAF 17.0   20.4 30th 4.0   -3.1 9th 28.8
Riverview Observatory 16.6 -0.1 20.2 30th 6.6 +0.2 2.9 8th 267.6 85.9 v high 312%
Springwood (Valley Heights) 15.5   18.5 29th 6.3   0.9 9th 26.0 56.8 average 46%
Sydney (Observatory Hill) 17.4 +1.1 21.4 31st 8.6 +0.6 5.5 8th 282.2 98.6 v high 286%
Sydney Airport AMO 17.2 +0.2 21.2 4th 8.6 +1.5 5.4 15th 228.0 71.0 v high 321%
Sydney Olympic Park (Sydney Olympic Pk A 17.2   21.4 31st 7.7   4.1 8th 172.0
Terrey Hills AWS 15.3   19.6 31st 7.1   1.9 9th 210.6

Daily rainfall
Hunter (61)12345678910111213141516171819202122232425262728293031
Webbs Ck-Wisemans Ferry (Hawkesbury Rive 0.5 3.0 - - - - - - - - - - - - - 3.0 - - 0.5 10.5 2.0 42.5 6.5 - - - - - - - -
Central Tablelands (South) (63)12345678910111213141516171819202122232425262728293031
Sackville Ferry (Hawkesbury River) - 1.2 - 0.2 - - - - - - - - - - - 2.4 0.2 0.2 0.2 16.2 1.2 30.2 4.0 0.4 - - - - - - -
Springwood (Valley Heights) 0.6 1.2 - - - - - - - - - - - - - 2.8 0.8 0.2 - 3.0 0.4 12.4 4.6 - - - - - - - -
Valley Heights (Sun Valley Rd) 0.6 1.2 - -
- - -
- -
- - - 3.0
0.2
3.0 0.4 13.0 5.0 - 0.2 -
-
-
Metropolitan (East) (66)12345678910111213141516171819202122232425262728293031
Abbotsford (Blackwall Point Rd) 1.8














3.0

25.0
100 44.5 1.0






Ashfield Bowling Club


















60.1 31.7 102 43.6







Auburn (Rosnay Golf Club) - 1.0 1.0 - - - - - - - - - - - - 4.0 1.0 - - 23.0 10.0 62.0 20.0 - 1.0 - - - - 1.0 -
Audley (Royal National Park) 5.0 1.0 - - - - - - - - - - - - - 7.0 - - 1.0 47.0 21.0 90.0 41.0 - - 1.0 4.0 - - - -
Avalon (Wollstonecraft Ave) 3.0 16.0 - - - - - - - - - - - - - 16.0 2.0 1.0 1.0 67.0 44.0 75.0 41.0 1.0 - - - - - - -
Avalon Beach (Avalon (Palmgrove Rd)) 4.0 13.2
















60.4 43.6 75.0








Bankstown Airport AWS 1.2 1.2 - - 2.2 - - - - - - - - - - 2.4 1.0 - - 21.4 7.6 50.0 23.6 1.0 0.2 - - - - - -
Belrose (Evelyn Place) 1.2 5.6

0.2








0.4 11.0 1.6 1.0
68.0 28.6 128 44.0 0.6





-
Campbelltown (Ingleburn (Long Point)) 1.0 - - - - - - - - - - - - - - 3.0 - - 2.0 27.0 12.0 53.0 23.0 1.0 - 2.0 1.0 - - - -
Canterbury Racecourse AWS 0.8 2.6 - - - - - - - - - - - - - 6.8 1.4 0.4 - 50.8 27.0 88.6 0.4 - 0.2 0.2 - - - - -
Castle Cove (Rosebridge Ave) 1.0 7.0











0.5 9.0 2.0 1.0
67.0 51.0 129 49.0 2.0 1.0





Chatswood Bowling Club 1.0 7.0 - - - - - - - - - - - - - 5.0 2.0 1.0 - 82.0 31.0 115 55.0 1.0 - 3.0 - - - - -
Collaroy (Long Reef Golf Club) 1.2 17.2











0.8 11.2 4.0 0.4
62.0 38.8 60.4 58.6 4.2






Concord Golf Club 0.8













8.6 1.4

48.0 24.8 87.8 31.2 0.8 0.6





Cronulla South Bowling Club













2.0 9.4 »» 3.4 2.6 71.0 60.0 126 35.0
1.4 1.0 1.0



Guildford (Woodville Golf Club) 1.0 1.0 - - - - - - - - - - - - - 4.0 1.0 - - 23.0 8.0 57.0 21.0 - - - - - 1.0 - -
Holsworthy Control Range 0.4 - - 0.2 - - - - - - - - - - - 1.6 0.6 - - 19.2 7.0 46.2 18.0 0.6 0.2 0.6 0.2 0.2 - 0.2 -
Lidcombe (Carnarvon Golf Club) 1.0 1.0 - - - - - - - - - - - - - 3.0 1.0 1.0 - 14.0 10.0 38.0 14.0 - - - - - - - -
Liverpool-Scrivener St (Georges River) 1.0 - - - - - - - - - - - - - - - 1.0 1.0 - 15.0 5.0 43.0 18.0 1.0 - - - - - - -
Lucas Heights (ANSTO) 0.4 1.0












5.2 0.8
0.1 33.8 18.8 66.0 36.0

1.0 1.4



Macquarie Park (Willandra Village) 0.6














6.0

61.6 25.2
30.8 0.6






Manley / Warringah (Allambie) 1.0 7.5 - - - - - - - - - - - - - 10.0 3.0 1.0 0.5 49.0 23.0 92.0 45.5 - - 0.5 - - - - -
Manley / Warringah (Belrose) 1.0 6.0 - - - -
- - - - - - - - 10.0 1.0 2.0 - 61.5 28.0 112 39.0 0.5
-
- - - -
Marrickville Golf Club 1.0 3.0 1.0 - - - - - - - - - - - 1.0 8.0 1.0 1.0 - 66.0 30.0 105 45.0 - 1.0 - - - - - 1.0
Mona Vale Golf Club 2.0 10.4 0.6 - 0.8 - - - - - - - - - 0.8 27.6 2.8 0.2 - 56.2 45.2 90.4 48.0 1.8 - - - 0.2 0.2 0.4 -
Parramatta (Erts) - 0.5 - - - - - - - - - - - - - 2.0 0.5 - - 13.0 5.5 31.0 14.0 - - - - - - - -
Parramatta North (Masons Drive) 0.4 1.4 - - - - - - - - - - - - - 5.8 1.3 0.3 0.1 28.4 16.2 51.2 25.0 0.2 - 1.8 - - - - -
Peakhurst Golf Club 3.0 3.0 1.0 - - - - - - - - - - - - 9.0 1.0 - - 30.0 19.0 72.0 25.0 - 1.0 - - - - - -
Randwick Bowling Club 1.0 4.6











1.4 12.4 4.8 1.8
62.4 51.2 81.8 69.0 2.6
0.4




Riverview Observatory 1.6 2.0 - - - - - - - - - - - - 0.6 8.6 2.2 2.0 - 73.5 21.6 107 47.2 0.8 - - - 0.6 0.1 - -
Rose Bay (Royal Sydney Golf Club) 2.0 2.4 0.2










1.8 13.8 4.8 1.2 1.8
35.8 81.6 61.2 2.6 0.2 0.6




Sans Souci (Public School) 2.0 5.0 - - - - - - - - - - - - - 19.0 1.0 1.0 - 56.0 36.0 101 32.0 - - 1.0 - - - - -
St Ives (Richmond Avenue) 0.8 4.6
0.2 0.2








1.0 9.8 1.8

73.2 27.0 101 41.6 0.6





-
Strathfield Golf Club 1.0 2.0 - - - - - - - - - - - - - 5.0 1.0 1.0 - 39.0 22.0 64.0 24.0 - - - - - 1.0 - -
Sydney (Observatory Hill) 0.4 2.6 - 0.2 - - - - - - - - - - 0.8 9.0 2.2 1.4 0.6 76.8 39.2 88.2 57.4 2.0 0.6 0.6 0.2 - - - -
Sydney Airport AMO 2.2 4.2 0.2 - - - - - - - - - - - 0.4 4.8 1.4 0.2 - 56.8 33.2 81.2 41.8 1.0 - 0.4 0.2 - - - -
Sydney Olympic Park (Sydney Olympic Pk A 0.2 1.2 0.2 - - - - - - - - - - - - 4.8 1.6 0.6 - 43.2 22.0 68.4 29.4 - 0.4 - - - - - -
Terrey Hills AWS

0.2 - 0.8 - - - - - - - - - - 6.4 2.0 0.6 0.2 51.0 18.6 130
0.2 - -
- 0.2 - -
Turramurra (Kissing Point Road)

5.4










0.4 5.0 1.4 0.4
75.0 23.0 102 44.0 0.6





-
Metropolitan (West) (67)12345678910111213141516171819202122232425262728293031
Abbotsbury (Fairfield City Farm) 1.0 - - - - - - - - - - - - - - - - - - 13.0 4.0 40.0 13.0 - - - - - - - -
Badgerys Creek AWS 0.2 0.6 - - - - - - - - - - - - - 0.8 0.2 - 0.4 7.4 1.0 28.4 7.4 - 0.2 - - 0.2 - 0.2 -
Baulkham Hills (Swimming Pool ) - 0.5 0.5 - - - - - - - - - - - - 3.0 0.5 - - 26.0 9.5 50.0 21.0 1.0 - - - - - - -
Baulkham Hills Eucalyptus Ct - 1.5 - - - - - - - - - - - - - 4.5 0.5 - - 24.0 8.0 43.0 16.5 1.5 - - - - - - -
Berowra (Goodwyn Road) 5.2 4.2












4.6 1.4 0.5
45.8 14.4 65.2 24.2







Blacktown (Dog Pound) 1.0 - 0.5 - - - - - - - - - - - - 2.5 - - - 15.0 4.5 40.5 14.5 1.0 - 0.5 - - - - -
Box Hill (Hynds Road) - 1.0 - - - - - - - - - - - - - 1.0 - - - 16.0 2.0 33.0 8.0 1.0 1.0 - - - - - -
Castle Hill (Kathleen Ave) 0.4












0.4 2.2 0.8 0.2
28.4 11.6 53.8 21.8 1.4






Glenorie (Old Northern Rd)
3.2












2.0 1.0

38.0 11.4 49.0 14.0







Greystanes (Cumberland Golf Club) 0.5 0.5 - 0.5 - - - - - - - - - - - 1.5 - 0.5 - 18.5 5.0 47.5 19.0 1.5 - - - - - - -
Hawkesbury River (Sackville Downstream) - 1.0 - - - - - - - - - - - - - 1.5 - 0.5 - 9.5 1.0 28.5 4.0 0.5 - - - - -

Horsley Park Equestrian Centre AWS 1.4 0.2 0.2 0.2 -
- - - - - - - - - 1.2 0.2 - 0.2 12.4 3.8 43.0 12.6 0.6 - 0.2 - - - - -
Kelso Ck (Kelso Creek U/S Levee (Georges 1.0 1.0 - - - - - - - - - - - - - 3.0 1.0 - 0.5 19.5 8.0 44.5 22.0 - 0.5 0.5 - - 0.5 - -
Kings Langley (NSW Soccer Federation) - 1.0 - - - - - - - - - - - - - 3.0 - 0.5 - 21.0 6.0 42.0 14.0 1.0 - 0.5 - - - - -
Kings Langley (Solander Rd) 0.2 1.0 0.2 - - - - - - - - - - - - 3.6 0.4 0.2 - 20.6 5.6 41.6 14.6 1.2 - - - - - - -
Liverpool (Michael Wenden Centre) 1.0 0.6 0.2 - - - - - - - - - - - - 1.2 0.8 - »» 14.2
38.4 13.2 1.0 0.6 0.3 - - 0.2 - -
Lower Portland (Hawkesbury River) 0.4 2.4 - 0.2 - - - - - - - - - - - 3.4 0.6 0.2 - 18.2 1.2 36.4 6.6 0.6 0.2 0.2 - - - - 0.2
Maroota (Tobruk) 0.8 0.6 0.6 0.4 0.4 0.2 - - - - - - - - - 0.8 1.0 0.8 0.6 0.8 0.8 0.8 0.8 0.8 0.6 0.8 0.6 0.6 0.4 0.6 0.4
Merrylands West (Finlayson Creek) 1.0 1.0 - - - - - - - - - - - - - 1.5 1.0 - - 27.5 10.5 71.0 29.5 3.0 - - - - - - -
North Parramatta (Burnside Homes) 0.5 0.5 0.5 - - - - - - - - - - - - 5.5 1.0 - - 26.0 12.0 48.0 21.0 0.5 - 1.5 - - - - -
North Rocks (Muirfield Golf Club) 0.5 1.0 - - - - - - - - - - - - - 4.0 0.5 0.5 - 37.5 17.5 60.0 29.0 0.5 - - - - - - -
Northmead Bowling Club 0.5 1.0 - - - - - - - - - - - - - 5.5 0.5 - - 23.0 9.0 42.5 18.0 1.0 - 1.0 - - - - -
Parramatta (Baulkham Hills West (Sierra - 1.0 - 0.5 - - - - - - - - - - - 3.5 0.5 - - 19.5 5.5 40.0 14.5 1.5 - - - - - - -
Penrith Lakes AWS 0.4 - 0.4 - - - - - - 0.2 - - - - - 1.6 0.2 0.2 0.2 2.8 0.4 17.4 2.2 - 0.2 0.2 - 0.2 0.4 - 0.2
Prospect Reservoir 0.9 1.0 0.1 - - - - - - - - - - - - 3.2 0.4 - - 16.1 5.6 39.0 16.2 2.4 0.1 0.2 - - - - -
Richmond RAAF - 0.8 - 0.2 - - - - - - - - - - - 1.0 0.2 0.2 - 5.4 0.2 16.8 3.8 - - - - - 0.2 - -
Seven Hills (Radio FM 103.2) 0.5 0.5 - - - - - - - - - - - - - 2.0 0.5 - - 14.5 5.0 38.0 14.0 1.5 - - 0.5 - - - -
Seven Hills (Collins St)














4.0


17.2 5.4 37.6 18.6 1.6






South Creek (Elizabeth Drive) - 0.1 - - - - - - - - - - - - - - - - - 0.7 0.1 3.1 0.7 - - - - - - - -
St Clair (Juba Close) - - - - - - - - - - - - - - - 2.0 - - - 2.0 1.0 19.0 5.0 1.0 - - - - - - -
Toongabbie Bowling Club - 1.0 - - - - - - - - - - - - - 3.5 0.5 - - 18.5 5.5 38.5 15.0 1.5 - 0.5 - - - - -
Toongabbie Ck (Redbank Road (Toongabbee - 0.5 - 0.5 - - - - - - - - - - - 4.0 1.0 - - 21.5 8.5 46.0 17.5 1.0 - 0.5 - - - - -
West Pennant Hills (Cumberland S F Alert 0.5 0.5 0.5 - - - - - - - - - - - - 2.0 1.5 - - 35.5 15.0 59.5 30.0 - - - - - - - -
Willmot (Resolution Ave) - - - - - - - - - - - - - - - - - 4.0 - 4.0 1.0 20.0 4.0 1.0 - -
- - - -
Windsor SWC (Hawkesbury River) - - - - - - - - - - - - - - - - - - - - - - - - - - - - 2.0 2.0 2.0
Illawarra (68)12345678910111213141516171819202122232425262728293031
Camden Airport AWS 0.6 - 0.2 - 0.6 - - - - - - - - - - 1.6 0.2 - 1.0 11.0 1.0 22.4 6.4 - 0.2 1.0 - - 0.2 - -
Camden Valley Golf Resort - - 1.0 - - - - - - - - - - - - 1.0 - 1.0 1.0 12.0 1.0 28.0 8.0 1.0 - 2.0 - - - - -
Campbelltown (Kentlyn (Georges River Roa - - 1.0 - - - - - 51.0 - - - -



- 1.0 -


- - 2.0 - - - 1.0 -
Campbelltown (Mount Annan) 1.4 0.2 - - - - - - - - - - - - - 0.6 1.2 - 0.6 15.4 2.4 28.0 10.2 0.4 - 1.2 0.2 - 0.2 - 0.2
Rossmore (South Creek) - 1.0 - - - - - - - - - - - - - 1.0 - - - 8.0 2.0 35.0 7.0 - - 1.0 - - - - -

Most values are the precipitation in the 24 hours to 9 am on the day indicated. Days marked with »» are part of a longer accumulation, which is marked like this on the final day. Values over 100 mm have been rounded to the nearest whole millimetre. Days marked with - have a rainfall report of zero; days left blank have no rainfall report (which often indicates no rain fell).
This table is very wide; you may have to scroll sideways to see all the days, and you may need to set the paper to 'landscape' to print.


Notes

A Monthly 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 Monday 1 August 2011. 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 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.

Further information

Media
(03) 9669 4057
Enquiries