Tuesday 1 April 2008 - Monthly Climate Summary for Sydney extremes - Product code IDCKGC1xx0

Sydney has dry, mild and sunny March

 

Details

  • Mild, sunny month with slightly below average temperatures
  • Below average rainfall
  • Sunniest March on record, averaging 8.9 hours of sunshine per day

Rainfall

The total March rainfall of 63.4 mm at Sydney Observatory Hill was well below the historic March average1 of 130 mm. There were 11 rain days during the month, slightly below the March average of 13 rain days. Below average rainfall occurred over most of the metropolitan area but totals were closer to the average in the west and south where storms were more active. Totals ranged from 116 mm at Cronulla in the south to a low of only 28.0 mm at Avalon on Sydney's northern beaches.

The dry conditions in Sydney were caused mainly by a blocking high pressure system maintaining stable conditions over NSW for most of the month with most rain-bearing systems being directed SE away from the state.

The Warragamba Dam catchment recorded only light rain during March contributing to a slight fall in storage levels. Monthly totals over the entire catchment were generally 20 - 50 mm. Recent rainfall in Sydney's drinking water catchments can be found on the Sydney Catchment Authority web site http://www.sca.nsw.gov.au/dams/rainfall.html.

Temperatures

Average to slightly below average maximum temperatures were recorded over the Sydney metropolitan area during March. The average maximum temperature at Observatory Hill was 25.1°C, which is slightly below the historic1 average maximum. Although maximum temperatures averaged a degree or two higher in the western suburbs, they were still close to or slightly below the normal for March.

As an indication of the mild conditions over the past 5 months, the maximum temperature in Sydney did not exceeded 31°C for the period 1 November 2007 to 31 March 2008. The last time Sydney experienced such conditions was back in 1872−73. Normally Sydney would expect 10 days over the 5 month period with temperatures exceeding 31°C.

Night-time temperatures were below the historic average over the whole Sydney metropolitan area during March. The average minimum temperature of 17.4°C at Observatory Hill was 0.6°C below the historic1 March average. Clear skies and light winds contributed towards the below average night-time temperatures, especially in the west. The average minimum temperature at Richmond was 14.2°C, the coolest for March for 12 years.

The highest temperature at Sydney (Observatory Hill) during March was 28.1°C on the 20th while the lowest overnight temperature was 12.8°C on the 1st. Corresponding extremes in the Sydney metropolitan area ranged from a daytime high of 33.2°C at Penrith Lakes on the 20th to an overnight low of 5.9°C at Camden Airport on the 31st.

Wind

The prevailing direction over coastal Sydney during the afternoons was SE - NE for 70−80% of the time, which is above the normal frequency of 65% from this direction. The highest wind gust recorded was 74 km/hr at Sydney Airport on the 21st associated with a strong southerly change.

Other phenomena

Four thunderstorms were reported from the official Sydney city site during March, against an historic average of 2 storms. A severe storm on the 7th caused heavy rain in western and northern parts of Sydney with Berowra recording the highest metropolitan daily rainfall of 65 mm (to 9am 8th).

Generally cloudless skies prevailed in Sydney during March with the city experiencing its sunniest March on record. The average sunshine of 8.9 hours per day was well above the historic average of 6.8 hours per day. Previous sunniest March was 8.7 hours per day in 1981 (sunshine records date from 1912).

Further information

Mike De Salis
Climate Information Officer
NSW Climate Services Centre
Bureau of Meteorology
Phone (02) 9296 1555
Email mikede@bom.gov.au

Extremes for the Sydney area

Hottest day
Highest temperature
33.2°C at Penrith Lakes AWS on the 20th
Warmest days on average
Highest mean daily maximum temperature
27.3°C at Penrith Lakes AWS
Coolest days on average
Lowest mean daily maximum temperature
24.2°C at Terrey Hills AWS
Coldest day
Lowest daily maximum temperature
15.9°C at Springwood on the 21st
Coldest night
Lowest temperature
5.9°C at Camden Airport AWS on the 31st
Coolest nights on average
Lowest mean daily minimum temperature
13.4°C at Campbelltown (Mount Annan)
Warmest nights on average
Highest mean daily minimum temperature
17.5°C at Sydney Airport
Warmest night
Highest daily minimum temperature
20.3°C at Sydney Airport and on the 10th and 20th
Wettest overall
Highest total rainfall
116.3 mm at Cronulla South
Driest overall
Lowest total rainfall
28.0 mm at Avalon
Wettest day
Highest daily rainfall
64.8 mm at Berowra on the 8th
Highest wind gust
74 km/h at Sydney Airport on the 21st

Records

Nil


Summaries for the Sydney area

This table is very wide and may not fit if printed.

Summary statistics for March 2008
Maximum temperatures
for March
(°C)
Minimum temperatures
for March
(°C)
Rainfall
for March
(millimetres)
Mean for
March
2008
Diff
from
normal
Highest for
March
2008
Mean for
March
2008
Diff
from
normal
Lowest for
March
2008
Total for
March
2008
Normal
for
March
Rank of
March
2008
Fraction of
March
normal
Sydney (Observatory Hill) 25.1 −0.1 28.1 20th 17.4 −0.6 12.8 1st 63.4 130.3 normal 49%
Camden Airport AWS 26.5 −0.2 31.9 20th 13.6 −1.2 5.9 31st 51.6 86.9 normal 59%
Parramatta 26.3 +0.1 31.5 6th 14.5 −1.3 9.3 31st 65.6 109.1 normal 60%
Richmond RAAF 26.7 −0.3 32.1 20th 14.2 −1.6 6.0 31st 45.2 92.1 low 49%
Springwood* 25.0   30.2 20th 14.1   8.9 30th 53.6 126.0 low 43%
Terrey Hills AWS* 24.2   29.6 20th 15.3   10.7 1st 58.4

* new stations, no historic average temperatures available and no historic average rainfall available for Terrey Hills

Additional climate data for Sydney (Observatory Hill) for March 2008
 

March 2008

Normal for March

Number of rain days

11
13

Average sunshine (hours per day)*

8.9
6.8

Average humidity at 3pm (%)

59
62

Number of thunderstorms

4
2

Number of windy days*

4
5

* recorded at Sydney Airport


Notes

This statement has been prepared based on information available at 10 am on Tuesday 1 April 2008. Some checks have been made on the data, but it is possible that results will change as new information becomes available.

1Averages:  historic average temperatures for Observatory Hill and Richmond are based on the period 1961 to 1990 which is a convention of the World Meteorological Organisation.  Average temperatures for Parramatta are based on all available data, 1968 - 2007 and Camden 1972 - 2007.  Rainfall averages and extremes for Observatory Hill are based on all years of record 1859 - 2007.

Normals 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 "normal" 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, normal in decile 4 to 7, high in decile 8 or 9 and very high is in decile 10).
The Fraction of normal shows how much rain has fallen this time as a percentage of the long-term mean.

Further information

NSW Climate Services Centre
Bureau of Meteorology
Phone (02) 9296 1555
Email mikede@bom.gov.au