Unseasonably warm and dry April

  • Very much above average maximum and minimum temperatures.
  • Below average rainfall.
  • Equal 7th warmest April on record.
  • Equal 6th warmest April on record for average maximum temperatures.

Rainfall

Sydney Observatory Hill recorded 30.0 mm in April which is well below the historical average1 of 132.9 mm. The overall dry conditions were partly due to the passage of several high pressure systems which brought mostly fine weather to Sydney and blocked any potential troughs or frontal systems. The rain fell on 10 days which is below the historical average1 of 12 days. The rainfall distribution over the Sydney area varied only slightly with most areas recording between 5 to 30 mm which corresponded to mostly below to very much below average rainfall for these areas (for more information see summary statistics table below). The wettest day in April was the 25th where locations such as Sackville recorded just over 20 mm during the passage of a cold front.

Sydney's storage levels have dropped to 57.6% following a dry March. 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

Temperature

Sydney Observatory Hill recorded an average mean temperature (average of maximum and minimum temperatures) of 20.2°C which is 1.0°C above the historical average1 of 19.2°C. This is the equal 7th warmest April on record and the warmest since 2004 (20.2°C). The above average temperatures are a result of the passage of several high pressure system ridging across the NSW coast which brought mostly fine conditions across Sydney. A lack of any significant cool changes throughout April contributed to the build up of heat and persistent warm condtions. Sea surface temperatures off the NSW coast have been above average and have contributed to the higher humidity which has kept temperatures above average particularly at night. A moderate El Niño in the Pacific ocean combined with human induced global warming have also contributed to the above average temperatures.

Maximum temperature

Sydney Observatory Hill recorded an average maximum temperature of 24.6°C which is 1.4°C above the historical average1 of 23.2°C. This is the warmest April since 2006 (24.6°C) and ranks as the equal 6th warmest April on record. Warm conditions were experienced across the Sydney area with Penrith recording the warmest average maximum temperature of 25.5°C. The highest daily maximum temperature recorded was 31.5°C at Bankstown Airport on the 22nd of the month.

Minimum temperature

Sydney Observatory Hill recorded an average minimum temperature of 15.9°C which is 0.7°C above the historical average1 of 15.2°C. This is the warmest April since 2002 (16.4°C). Warm minimum temperatures were recorded across the Sydney basin with Sydney Observatory Hill recording the warmest average minimum temperature across greater Sydney. The warmest daily minimum temperature was 20.2°C recorded at Sydney Observatory Hill on the 24th of the month.

Wind

Prevailing winds in coastal Sydney during the afternoon (3pm) were E and S for 66% of the time during April which is above the normal frequency from this direction (observations taken from Sydney Airport).

Other phenomena

On the morning of the 21st of the month fog was observed at many locations across greater Sydney.

Further information

Media
(03) 9669 4057
Enquiries

Extremes in April 2010
Hottest day 31.5 °C at Bankstown Airport AWS on the 22nd
Warmest days on average 25.5 °C at Penrith Lakes AWS
Coolest days on average 22.8 °C at Terrey Hills AWS
Coldest day 16.9 °C at Terrey Hills AWS on the 30th
Coldest night 4.0 °C at Camden Airport AWS on the 27th
Coolest nights on average 10.9 °C at Camden Airport AWS
Warmest nights on average 15.9 °C at Sydney (Observatory Hill)
Warmest night 20.2 °C at Sydney (Observatory Hill) on the 24th
Wettest overall 47.7 mm at Avalon Beach (Avalon (Palmgrove Rd))
Wettest day 21.6 mm at Sackville Ferry (Hawkesbury River) on the 25th
Highest wind gust 61 km/h at Sydney Airport AMO on the 8th
61 km/h at Sydney Airport AMO on the 11th




Summary statistics for April 2010
Maximum temperatures
for April
(°C)
Minimum temperatures
for April
(°C)
Rainfall
for April
(millimetres)
Mean for
April
2010
Diff
from
average
Highest for
April
2010
Mean for
April
2010
Diff
from
average
Lowest for
April
2010
Total for
April
2010
Average
for
April
Rank of
April
2010
Fraction of
April
average
Badgerys Creek AWS 25.2   30.4 23rd 11.3   4.2 27th 14.6
Bankstown Airport AWS 24.6 +1.0 31.5 22nd 13.3 +0.6 6.9 28th 5.0 82.8 v low 6%
Camden Airport AWS 25.2 +1.4 30.4 23rd 10.9 -0.1 4.0 27th 12.0 64.4 low 19%
Campbelltown (Mount Annan) 25.3   30.8 23rd 11.3   4.5 27th 11.0
Canterbury Racecourse AWS 24.4   30.0 23rd 13.0   7.0 29th 19.4
Holsworthy Control Range 24.8   30.2 23rd 12.3   5.1 28th 14.8
Horsley Park Equestrian Centre AWS 24.8   29.6 23rd 12.9   7.3 13th 16.2
Liverpool (Michael Wenden Centre) 25.2   30.5 23rd 12.2   1.6 27th 15.6
Parramatta North (Masons Drive) 24.7 +0.9 30.0 22nd 13.1 +0.3 7.6 27th 31.6 86.8 low 36%
Penrith Lakes AWS 25.5   31.3 24th 13.1   7.1 27th 15.4
Prospect Reservoir 25.2 +1.6 29.7 23rd 13.3 +0.3 8.1 27th 22.1 74.0 low 30%
Richmond RAAF 24.7   29.6 23rd 11.8   4.6 27th 16.2
Riverview Observatory 24.3 +1.6 30.1 23rd 13.8 +0.9 8.9 27th 37.1 107.0 low 35%
Springwood Bowling Club 23.3   28.7 23rd 13.0   8.8 13th 17.2 87.9 low 20%
Sydney (Observatory Hill) 24.6 +2.2 30.7 23rd 15.9 +1.2 11.7 27th 29.8 125.8 low 24%
Sydney Airport AMO 24.2 +1.3 30.2 23rd 15.7 +1.6 11.0 27th 33.4 104.7 low 32%
Sydney Olympic Park (Sydney Olympic Pk A 24.9   30.7 23rd 15.0   10.4 27th 25.8
Terrey Hills AWS 22.8   28.3 23rd 14.1   10.1 12th 20.6

Daily rainfall

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.

Hunter (61)123456789101112131415161718192021222324252627282930
Webbs Ck-Wisemans Ferry (Hawkesbury Rive - - - 0.8 0.8 - 0.5 - - - - - - - - - - - - - 0.5 - - - 3.0 0.5 - - - -
Central Tablelands (South) (63)123456789101112131415161718192021222324252627282930
Sackville Ferry (Hawkesbury River) - - - 0.6 0.4 - 9.4 4.8 - - - - - - - - - 0.2 0.2 - 0.2 0.2 - 0.2 21.6 0.6 0.2 - 0.2 0.2
Springwood Bowling Club 0.2 - - 0.8 - - 10.0 2.8 - - - - - - - - - - - - - - - - 3.2 0.2 - - - -
Valley Heights (Sun Valley Rd) 0.8
- 1.0

10.8




-
-


-
- - -
6.4
-
-
Metropolitan (East) (66)123456789101112131415161718192021222324252627282930
Abbotsford (Blackwall Point Rd)



3.4 0.4 3.0 5.0 2.0














10.4 1.0



Auburn (Rosnay Golf Club) - - - 4.0 - - 7.0 2.0 1.0 - - - - - - - - - - - - - - - 7.0 1.0 - - - -
Audley (Royal National Park) - - - 11.0 1.0 3.0 3.0 1.0 7.0 - - - - - - - - - - - 1.0 - - - 4.0 1.0 - - - -
Avalon Beach (Avalon (Palmgrove Rd)) 0.8
»» »» »» 14.0 »» »» 10.6






1.0





0.3 20.0 1.0 -


Bankstown Airport AWS - - - 2.6 0.4 -

2.0 - -
- - - - - - - - - - -



- - -
Belrose (Evelyn Place) 0.6

8.8 3.8 0.6 8.2 6.4 0.8









0.2



11.2



-
Campbelltown (Ingleburn (Long Point)) - - - 2.0 - - 6.0 1.0 2.0 - - - - - - - - - - - - - - - 4.0 - - - - -
Canterbury Racecourse AWS 0.2 - -
1.6
4.0 3.4 1.8 - - - -
- -
- - - - - - - 8.4
- - -
Castle Cove (Rosebridge Ave)


7.0
1.2
14.0 2.0




















Chatswood Bowling Club - - - 7.0 4.0 - 5.0 4.0 2.0 - - - - - - - - - - - 1.0 - - - 10.0 - - - - -
Collaroy (Long Reef Golf Club)


4.2
1.0 5.6 4.0 1.6






0.2






10.2



1.0
Concord Golf Club


8.2

5.4 2.8 1.2




















Guildford (Woodville Golf Club) - - - 3.0 - - 6.0 3.0 8.0 2.0 - - - - - - - - - - - - - - 6.0 1.0 - - - -
Holsworthy Control Range - - - 3.0
- 7.0 2.0 2.4
- - - - - - -
- 0.2
- - -
0.2 - - -
Lidcombe (Carnarvon Golf Club) - - - 2.0 1.0 - 5.0 2.0 1.0 - - - - - - - - - - - - - - - 5.0 - - - - -
Liverpool-Scrivener St (Georges River) - - - 2.0 - - 1.0 - - - - - - - - - - - - - - - - - - - - -

Lucas Heights (ANSTO)


1.5 1.0
3.0 1.7 3.8






1.0






5.0




Manley / Warringah (Allambie) 1.5 - - 7.0 1.0 1.5 7.0 10.5 1.5 - - - - - - - - - - - - - - - 9.0 - - - - -
Manley / Warringah (Belrose) 0.5 - - 5.5 2.0 0.5 4.0 5.5 0.5 - - - - - - - - - - - 0.5 - - - 7.5 0.5
- -
Marrickville Golf Club - - - 9.0 2.0 - 3.0 3.0 5.0 - - - - - - - 1.0 - - - 1.0 - - - 7.0 1.0 - - - -
Mona Vale Golf Club - - - 3.8 - 3.0 9.6 4.0 0.4 - - - - - - - 0.2 - - - 0.2 - - - 13.8 0.2 - - - 0.2
Parramatta (Erts) - - - 2.0 1.5 - 5.0 2.5 3.5 - - - - - 4.0 - - - - - - - - - 7.5 0.5 - - - -
Parramatta North (Masons Drive) 0.2 - - 5.4 2.2 0.2 5.4 5.8 2.6 - - - - - - - - - - - - - - - 9.2 0.6 - - - -
Peakhurst Golf Club - - - 6.0 2.0 - 4.0 2.0 3.0 - - - - - - - - - - - - - - - 6.0 - - - - -
Randwick Bowling Club 0.6

7.2 2.2 0.4 3.0

6.0





2.8






8.2 0.4


1.4
Riverview Observatory - -
12.1 4.0 0.4 6.6 1.4 1.8 - - - - - - - - - 0.2 0.4 0.2 0.2 - - 9.2 0.6 - - - -
Rose Bay (Royal Sydney Golf Club) 0.6
0.6 12.0 1.2 0.8 4.8 3.2 2.6






6.0
0.2
0.4








Sans Souci (Public School) - - - 7.0 3.0 2.0 5.0 1.0 9.0 - - - - - - - - - - - - - - - 6.0 - - - - -
St Ives (Richmond Avenue) 0.2
0.2 6.0 0.4 0.8 8.0 2.6 0.4














12.8 1.4


-
Strathfield Golf Club - - - 4.0 2.0 - 6.0 2.0 2.0 - - - - - - - - - - - - - 2.0 - 9.0 - - - - 2.0
Sydney (Observatory Hill) 0.2 - - 6.8 1.2 0.8 3.8 3.0 4.4 - - - - - - - 0.6 - - - - - - - 8.8 0.4 - - - -
Sydney Airport AMO 0.2 - - 9.8 3.2 1.4 1.8 2.4 5.4 - - - - - - - 1.6 0.2 - - - - - - 7.2 0.2 - - - -
Sydney Olympic Park (Sydney Olympic Pk A - - - 8.6 0.8 0.8
2.6 1.2 - - - - - - - - - - 0.2 - - - - 11.6
- - - -
Terrey Hills AWS 0.4 - 0.2 8.2 0.6 1.0 7.6 2.2 0.2 0.2 - - - - - - - - - - - - - - - - - - - -
Turramurra (Kissing Point Road) 0.8

6.0 1.6 0.8 7.0 6.6 0.6









1.6



11.4 0.6


-
Metropolitan (West) (67)123456789101112131415161718192021222324252627282930
Abbotsbury (Fairfield City Farm)



























- -
Badgerys Creek AWS - 0.2 - 0.4 0.2 - 9.8 1.6 - - - - - - - - - - - - 0.2 - 0.2
2.0 - - - - -
Baulkham Hills (Swimming Pool ) - - - 4.0 6.0 - 7.0 6.5 4.5 - - - - - 0.5 - - - - - - - - - 9.0 0.5 - - - -
Baulkham Hills Eucalyptus Ct - - - 2.0 0.5 - 7.0 10.0 7.5 - - - - - 2.5 - - - - - - - - - 8.0 0.5 - - - -
Berowra (Goodwyn Road)


4.0
2.0
1.2 7.4









1.2



14.6



-
Blacktown (Dog Pound) 0.5 - - 1.0 - - 8.0 3.0 0.5 - - - - - - - - - - - - - - - 8.0 0.5 - - - -
Box Hill (Hynds Road) - - - 1.0 - - 9.0







1.0 - - - - - - - - - - - - - -
Castle Hill (Kathleen Ave)

0.1 5.9 3.8
8.4 4.2 4.6









0.4



10.3 0.7



Glenorie (Old Northern Rd)


1.0

10.6 2.0 5.8









1.0



13.0



1.0
Greystanes (Cumberland Golf Club) - - - 1.5 - - 7.0 2.5 1.5 - - - - - - - - - - - - - - - 6.5 0.5 - - - -
Hawkesbury River (Sackville Downstream)
- - 0.5 - - 8.5 4.0 0.5 - - - - - - - - 0.5 - - - 0.5 - - 16.0 0.5 - - - -
Horsley Park Equestrian Centre AWS - - -
0.2 - 7.4 3.4
- - - - - - - - - - - 0.2 0.2 -
4.4 0.4 - - - -
Kelso Ck (Kelso Creek U/S Levee (Georges - - - 3.0 0.5 - 4.0 3.0 1.5 - - - - - - - - - - - - - - - 4.5 0.5 - - - -
Kings Langley (NSW Soccer Federation) 0.5 - - 2.0 - 0.5 8.0 7.0 10.5 - - - - - - - - - - - 0.5 - - - 8.5 1.0 - - - -
Kings Langley (Solander Rd) 0.4 - - 1.2 - 0.2 7.4 10.2 11.0 - - - - - - - - - - 0.2 - - - - 7.6 0.4 - - - -
Liverpool (Michael Wenden Centre) - - - - - - 6.0 4.0 - - - - - - - - - - - - - 1.0 - - 4.0 »» 0.6 - - -
Lower Portland (Hawkesbury River) 0.2 - - 0.4 0.2 - 7.6 5.0 0.2 - - - - - - - - - - - - - - - 17.0 0.4 - - 0.2 -
Maroota (Tobruk) 0.2 - - 1.6 - 0.2 12.6 3.0 0.2 - - - - - - - - - 0.4 0.4 0.4 0.2 - - 21.2 0.4 - - - -
Merrylands (Welsford Street)





6.4 5.4















13.8




Merrylands West (Finlayson Creek) - - - 1.0 1.0 - 9.5 3.0 6.0 1.0 - - - - - - - - - - - - - - 8.0 1.0 - - - -
North Parramatta (Burnside Homes) 0.5 - - 4.5 1.0 - 5.5 4.0 2.5 - - - - - - - - - - - - - - - 8.5 0.5 - - - -
North Rocks (Muirfield Golf Club) - - - 4.5 4.5 - 6.0 10.5 4.5 - - - - - - - - - - - - - - - 9.0 0.5 - - - -
Northmead Bowling Club - - - 2.5 0.5 0.5 5.0 3.5 3.5 - - - - - - - - - - - - 0.5 - - 7.5 - - - - -
Parramatta (Baulkham Hills West (Sierra - - - 1.5 - - 7.5 8.5 8.0 - - - - - 1.5 - - - - - - - - - 8.0 - - - - -
Penrith Lakes AWS - - - - - - 10.2 4.6
- - - - - - - - - - - - - 0.2

- - 0.2 - 0.2
Prospect Reservoir 0.5 - - 1.9 - - 8.4 3.9 0.8 - - - - - - - - - - - - - - - 6.2 0.4 - - - -
Richmond RAAF

- 0.2 -
10.4 - - - - - - - - - - - - - - - 0.2 - 5.0 0.4 - -
-
Seven Hills (Radio FM 103.2) - - - 0.5 0.5 - 7.0 3.0 1.0 - - - - 0.5 - - - - - - - - - - 7.5 - - - - -
Seven Hills (Collins St)


1.6

5.0 8.8















7.8




St Clair (Juba Close)











- - - - - - - - - - - - 4.0 - - - - -
Toongabbie Bowling Club - - - 1.0 - - 6.5 3.0 9.5 0.5 - - - - - - - - - - - - - - 7.5 0.5 - - - -
Toongabbie Ck (Redbank Road (Toongabbee - - - 2.0 1.0 - 6.0 4.5 5.0 0.5 - - - - 1.0 - - - - - - - - - 7.5 - 0.5 - - -
West Pennant Hills (Cumberland S F Alert - - - 5.5 2.0 0.5 7.0 6.0 2.5 0.5 - - - - - - - - - - - - - - 11.5 - - - - -
Willmot (Resolution Ave)












- - - - - - - - - - - 4.0 - - - - -
Windsor SWC (Hawkesbury River) - - - - - - 11.0 - - - - - - - - - - - - - - - - - 6.0 - - - - -
Illawarra (68)123456789101112131415161718192021222324252627282930
Camden Airport AWS - - - 0.8 - - 5.6 3.0 - - - - - - - - - - - - 0.2 - - - 2.2 0.2 - - - -
Camden Valley Golf Resort - - - - - - 5.0 1.0 - - - - - - - - - - - - - - - - 2.0 - - - - -
Campbelltown (Kentlyn (Georges River Roa - - - 1.0 - - 6.0 1.0 2.0 - - - - - - - - - - - 1.0 - - - 4.0 - - - - -
Campbelltown (Mount Annan) - - - 0.2 0.8 - 3.8 2.8 - - - - - - - - - - - - - - - - 3.2 0.2 - - - -
Rossmore (South Creek) - - - - - - 8.0 - - - - - - - - - - - - - - - - - 3.0 - - - - -

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 9 am on Monday 3 May 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.

Further information

Media
(03) 9669 4057
Enquiries