Wednesday, 1 May 2013 - Monthly Climate Summary for South Australia - Product code IDCKGC23R0
Rainfall totals were average to below average across South Australia through April 2013, as high pressure systems dominated the weather across the State throughout the month. Through the early part of April, weak low pressure troughs delivered only small rainfall totals across coastal areas. The wettest period occurred during the latter half of the month as a series of vigorous cold fronts resulted in moderate to high totals that were mainly concentrated about southern areas of the State.
The growing season, for crop farming in agricultural districts, is typically viewed as starting in April, often with a significant rain event occurring towards the end of April as the break to the season. This year, a low pressure trough followed by a cold frontal system that moved across the State during the third week of the month saw rainfall totals of 25mm or greater in a 3 day period across the Eyre and Yorke Peninsulas, parts of the Mount Lofty Ranges and across Kangaroo Island, but other areas did not see a definite break to the growing season occur in April 2013.
See a map of rainfall deciles.
Rainfall across the pastoral districts was mainly below above average, with totals generally ranging between 5 to 20 mm. However some locations south of Marree received monthly totals in excess of 60 mm, owing mostly to the passage of a low pressure trough which produced severe thunderstorms in the early part of the month. Blinman in the southern parts of the Far North pastoral observed the wettest day for any location in the State, with a record highest 55.8 mm in the 24 hours 9am on the 7th. Leigh Creek (Pfitzners Well) was the wettest across the pastoral with a monthly total 67.6 mm, 32 mm of which was also reported from thunderstorms in the early part of the month.
Some sites had their highest April daily rainfall on record.
Rainfall across the agricultural areas remained below average for the first half of the month; a series of cold frontal systems in the last 2 weeks increased totals for much of the Far west, the Eyre and Yorke Peninsulas, the Mount Lofty and Flinders Ranges and parts of the Murray Valley. Rainfall totals typically ranged between 10 to 30 mm, with higher values in the 40 to 60mm range about coastal and elevated locations. The wettest days occurred between the 21st and 24th and on the 29th of the month. Uraidla recorded the highest rainfall total for the month in the State with 73.4 mm, nearly half of which was observed in the 24 hours to 9am on the 22nd.Some sites had their highest total April rainfall for at least 25 years. Some sites had their lowest total April rainfall for at least 25 years.
The average temperature (the average of the daily maximum and daily minimum temperatures) for South Australia as a whole throughout April 2013 was 1.2 °C above the long-term average, the warmest April since 2010. By way of contrast, April 2012 saw temperatures average up to 0.7 °C above normal.
Maximum temperatures for the month were above average across the entire State, with Pastoral areas seeing daytime temperatures 2 to 3 °C warmer than usual. April daytime temperatures averaged across the State as a whole were the warmest since 2005 and the sixth warmest on record. Maximum temperatures ranged from 18.0 °C at Mount Lofty to 31.0°C at Marree Comparison in the Northeast pastoral district. The hottest day of the month for any location was observed at Ceduna AMO on the 12th where the maximum temperature reached 35.5 °C. Mount Lofty had the coldest day on the 21st with an observed maximum of 12.1°C.
See a map of maximum temperature anomalies.
Overnight minimum temperatures were widely above average across South Australia throughout April 2013, with some locations in the western parts, the Upper North and the Adelaide region observing minimum temperatures close to 2 °C above normal. Despite this, some locations near the eastern border and the lower southeast observed cooler than normal nights. The warmest period for most locations occurred between the 12th and 13th as a high pressure system located in the Tasman Sea maintained fine weather over most of South Australia. Coolest nights were observed on the 20th and 21st as a cool and moist west to southwesterly airstream, in the wake of a low pressure trough, moved through the State.
Night time minimum temperatures across South Australia ranged from 7.7°C at Coonawarra and Naracoorte Aerodrome in the south-east of the state to 16.4 °C on Neptune Island. Moomba Airport recorded the warmest night of the month with a minimum of 23.6°C on the 15th, while Naracoorte Aerodrome observed the coldest night of the month on the 20th with a minimum temperature of -3.0 °C.
See a map of minimum temperature anomalies.
|Extremes in April 2013|
|Hottest day||35.5 °C at Ceduna AMO on the 12th|
|Warmest days on average||31.0 °C at Marree Comparison|
|Coolest days on average||18.0 °C at Mount Lofty|
|Coldest day||12.1 °C at Mount Lofty on the 21st|
|Coldest night||-3.0 °C at Naracoorte Aerodrome on the 20th|
|Coolest nights on average||
7.7 °C at Coonawarra|
7.7 °C at Naracoorte Aerodrome
|Warmest nights on average||16.4 °C at Neptune Island|
|Warmest night||23.6 °C at Moomba Airport on the 15th|
|Warmest on average overall||
22.8 °C at Moomba Airport|
22.8 °C at Oodnadatta Airport
|Coolest on average overall||13.9 °C at Mount Lofty|
|Wettest overall||73.4 mm at Uraidla|
|Driest overall||0 mm at Ernabella (Pukatja)|
|Wettest day||55.8 mm at Blinman on the 7th|
|Highest wind gust||91 km/h at Neptune Island on the 21st|
|Record highest April daily rainfall|
Highest daily rainfall
in April 2013 (mm)
|Blinman||55.8||on the 7th||50.8||on the 4th in 1891||130|
|Cowell (Winter Springs)||27.2||on the 29th||21.0||on the 12th in 1998||44|
|Highest total April rainfall for at least 25 years|
for April 2013 (mm)
Most recent April
at least this wet
* note: there are gaps in the historical record at this site, so it is possible a higher value has gone unreported.
|Lowest total April rainfall for at least 25 years|
for April 2013 (mm)
Most recent April
at least this dry
|Port Elliot Caravan Park||2.0||0.0||in 1923||90||39.9|
|Summary statistics for April 2013|
|Northwest (district 16)|
|Coober Pedy Airport||28.7||33.7||14th||15.8||11.0||22nd||5.6|
|Roxby Downs (Olympic Dam Aerodrome)||28.9||33.4||8th||13.4||7.1||26th||2.6|
|Far North (district 17)|
|Leigh Creek Airport||28.0||+1.8||32.6||6th||13.4||+0.5||9.0||23rd||5.6||13.1||average||43%|
|Western Agricultural (district 18)|
|Coulta (Coles Point)||23.8||+1.6||30.1||11th||12.8||+1.0||7.1||17th||21.0|
|North Shields (Port Lincoln AWS)||23.5||+1.4||34.5||12th||13.0||+0.9||8.0||17th||16.8|
|Port Augusta Aero||27.2||34.3||12th||13.9||8.4||22nd||16.8|
|Upper North (district 19)|
|Northeast (district 20)|
|Gluepot Reserve (Gluepot)||25.5||32.0||13th||9.3||-1.0||20th||18.0|
|Lower North (district 21)|
|Clare High School||22.8||30.0||12th||10.3||5.5||26th||26.2|
|Port Pirie Aerodrome||25.8||33.0||12th||13.2||8.3||17th||19.1|
|Snowtown (Rayville Park)||24.9||32.4||6th||10.6||6.1||17th||20.8|
|Yorke Peninsula (district 22A)|
|Kangaroo Island (district 22B)|
|Parndana Cfs AWS||21.5||28.8||12th||10.4||5.5||17th||63.8|
|Adelaide Plains (district 23A)|
|Adelaide (Kent Town)||23.8||+1.1||32.1||12th||13.3||+0.9||9.1||20th||33.2||39.6||average||84%|
|County Light (district 23B)|
|Rosedale (Turretfield Research Centre)||24.1||+1.0||32.4||12th||11.3||+0.6||4.2||16th||40.9||36.5||average||112%|
|Mount Lofty Ranges (district 23C)|
|Hindmarsh Island AWS||21.6||31.4||12th||12.7||7.6||20th||26.6|
|Kuitpo Forest Reserve||20.1||28.5||12th||11.6||6.9||19th||31.4|
|Mount Crawford (Mt Crawford AWS)||20.2||28.6||12th||10.7||5.7||20th||54.4|
|Parawa (Second Valley Forest AWS)||19.0||26.7||6th||11.8||7.8||20th||72.2|
|Victor Harbor (Encounter Bay)||21.5||31.1||12th||10.8||5.1||17th||43.2|
|Upper Murray Valley (district 24A)|
|Loxton Research Centre||24.6||+0.7||31.8||6th||9.3||+0.9||-0.5||20th||17.8||16.0||average||111%|
|Lower Murray Valley (district 24B)|
|Murray Bridge (Pallamana Aerodrome)||23.9||32.9||12th||9.9||1.6||20th||15.6|
|Murray Bridge Comparison||24.7||+1.2||33.0||6th||11.0||+0.7||5.8||20th||23.0||28.7||average||80%|
|Murray Mallee (district 25A)|
|Upper Southeast (district 25B)|
|Lameroo (Austin Plains)||23.6||31.3||6th||9.5||2.9||20th||12.0|
|Lower Southeast (district 26)|
|Cape Jaffa (The Limestone)||20.6||+0.7||27.1||12th||11.4||+0.8||3.5||20th||37.0|
|Mount Gambier Aero||20.7||+1.2||29.5||6th||9.0||+0.3||1.8||20th||40.0||54.7||average||73%|
A Monthly Climate Summary is prepared to list the main features of the weather in South Australia 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 Wednesday 1 May 2013. 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
(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 being used for temperature area averages from December 2012 onwards. The major change from earlier datasets is that the ACORN-SAT dataset commences in 1910, rather than 1950, and hence rankings are calculated using a larger set of years.