Monday, 30 April 2012 - Monthly Climate Summary for Adelaide Metro & Hills - Product code IDCKGC16L0
Adelaide Metro & Hills in April 2012: A warm and dry month
- Below average rainfall, typically only 50% of average on the Adelaide plains, closer to average in the Adelaide hills.
- Daytime temperatures about 2 degrees above average, and above average numbers of hot days.
- Night time temperatures were near average.
The April 2012 rainfall total at Adelaide (Kent Town) was 27.0 mm received on 7 rain days. This is compared to the long-term average of 40.1 mm on 8 rain days, and the median rainfall of 33.6 mm. By comparison, during April 2011, 13.6 mm was recorded. April 2010 was the last April in Adelaide with above average rainfall with 49.6mm.
Most of the month saw only small rainfall totals from weak cold frontal systems. Much of the rainfall observed for the month came from a series of cold fronts around a strong cold air mass in the third week of the month. This event also produced significant totals in the Adelaide Hills in the persistent moist westerly airstream, resulting in totals for the month in this region being closer to average than on the plains where totals were typically only 50% of average.
Rainfall totals for April 2012 across the plains typically were ranged from 15 to 25mm with higher totals in the 25 to 50mm range in the Adelaide Hills. The wettest location for the month was Mount Barker where 49.2mm was recorded for the month, most of that occurring on the 22nd and 23rd of the month.
Note that the Adelaide official climate rainfall record is taken from the manually observed 203mm rain gauge at the Kent Town site in Adelaide. These figures may differ from totals on some Bureau of Meteorology web pages as these may be from automatic tipping bucket rain gauge readings.
Much of the month was very much warmer than average with maximum temperatures up to 6 degrees above average in the first week. Daytime temperatures remained about 2 to 3 °C above average for the month as a whole, despite a cooler burst of weather near months end associated with a strong cold air mass and sequence of cold fronts.
The mean maximum temperature recorded at the Adelaide (Kent Town) for April 2012 was 24.2°C, 1.6°C above the long-term mean maximum temperature of 24.6°C. In comparison, April 2011 saw average maximum temperatures of 22.8°C at Adelaide (Kent Town). The record highest April mean maximum in Adelaide is 26.9°C set in 1923 at the West Terrace site.
During April 2012, Adelaide (Kent town) recorded 4 days where the maximum temperature exceeded 30 °C against the expected long term average of 2 days above 30°C. The coldest day was reported on the 23rd when the maximum reached 16.5°C. The warmest day was on the 5th when 34.6°C was recorded for the maximum temperature.
The hottest day across the Adelaide and Hills region was reported at Edinburgh Airport with a maximum of 35.0 °C on the 5th, and the coldest day was at Mount Lofty on the 23rd with a maximum of 9.5 °C.
Mean minimum temperatures were generally within 1°C of the average this April. Some locations on the Adelaide Plains were slightly cooler than average, though hills locations tended to be warmer than average by about 1 °C owing to above average cloud cover.
The mean minimum temperature for April 2012 at Adelaide (Kent Town) was 12.6°C, just above the long term April average of 12.4 °C. April 2011 saw minimum temperature for the month of 12.3 °C.
The coldest minimum temperature recorded during April 2012 in the Adelaide and Hills area was 4.2°C on the 11th at Mt Barker, whilst the warmest night was 21.8°C at Noarlunga on the 6th.
|Extremes in April 2012|
|Hottest day||35.0 °C at Edinburgh RAAF on the 5th|
|Warmest days on average||24.9 °C at Parafield Airport|
|Coolest days on average||18.6 °C at Mount Lofty|
|Coldest day||9.5 °C at Mount Lofty on the 23rd|
|Coldest night||4.2 °C at Mount Barker on the 11th|
|Coolest nights on average||9.6 °C at Mount Barker|
|Warmest nights on average||13.8 °C at Noarlunga|
|Warmest night||21.8 °C at Noarlunga on the 6th|
|Warmest on average overall||18.5 °C at Noarlunga|
|Coolest on average overall||14.8 °C at Mount Lofty|
|Wettest overall||49.6 mm at Mount Barker|
|Driest overall||13.4 mm at Parafield Airport|
|Wettest day||25.8 mm at Mount Barker on the 23rd|
|Highest wind gust||74 km/h at Adelaide Airport on the 6th|
|Summary statistics for April 2012|
|Adelaide (Kent Town)||24.2||+1.6||34.6||5th||12.6||+0.2||7.6||24th||27.0||40.1||average||67%|
A Monthly Climate Summary is prepared to list the main features of the weather in Adelaide Metro & Hills 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 3 pm on Monday 30 April 2012. 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.