Perth in December 2014: Dry and mild

December 2014 was very dry across the Perth metropolitan area, with most sites recording little or no rainfall. The highest monthly total was 4.8 mm at Jarrahdale in the southern Perth hills. It was a rainless month at Perth Metro, the seventh year since records commenced in 1876 that Perth Metro has recorded no rainfall in December, and the driest December for five years, since no rainfall was recorded in December 2009.

Mean maximum temperatures for December were below average for most sites, with days mostly mild to warm for the first half of the month, whilst maximum temperatures were mostly in the low thirties in the second half of the month. Hot days were recorded on the 11th, 19th, 23rd to 27th, 29th and 30th for coastal plain and hills sites, and a daily maximum temperature of 43.4 °C at Pearce RAAF on the 30th was the highest temperature of the month in the Perth area. Perth Metro recorded a mean maximum temperature of 28.9 °C, which is just below the long-term average of 29.1 °C, and the mildest December for six years, since 2008, when a mean maximum temperature of 27.8 °C was recorded.

Mean minimum temperatures were generally below average across the Perth region in December 2014. Most nights were cool to cold with minima commonly in the 11 °C to 17 °C temperature range. Cold nights with daily minima below 10 °C were experienced at some coastal plain sites on the 14th and 16th, whilst Bickley in the Perth hills recorded four cold nights on the 9th and 10th, and 16th and 17th. A daily minimum temperature of 8.9 °C at Pearce RAAF on the 16th and at Bickley on the 17th was the lowest temperature of the month in the Perth Metropolitan area. Perth Metro recorded a mean minimum temperature of 15.8 °C, which is below the long-term average of 16.4 °C, and the coolest December for six years, since 2008, when a mean minimum of 15.6 °C was recorded.

  • A fire at Whiteman Park in the northern Perth suburbs burnt 367 hectares of bushland on 14 December.

Further information

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Extremes in December 2014
Hottest day 43.4 °C at Pearce RAAF on the 30th
Warmest days on average 31.1 °C at Pearce RAAF
Coolest days on average 24.6 °C at Rottnest Island
27.7 °C at Bickley
Coldest day 19.9 °C at Garden Island HSF on the 16th
20.9 °C at Bickley on the 15th
Coldest night 8.9 °C at Pearce RAAF on the 16th
8.9 °C at Bickley on the 17th
Coolest nights on average 13.1 °C at Bickley
Warmest nights on average 17.2 °C at Rottnest Island
15.8 °C at Perth Metro
Warmest night 23.6 °C at Gosnells City on the 20th
Warmest on average overall 22.7 °C at Gosnells City
Coolest on average overall 20.4 °C at Bickley
Wettest overall 4.8 mm at Jarrahdale
Wettest day 4.4 mm at Jarrahdale on the 2nd
Strongest wind gust 83 km/h at Rottnest Island on the 12th




Summary statistics for December 2014
Maximum temperatures
(°C)
Minimum temperatures
(°C)
Rainfall
(millimetres)
Mean for
December
2014
Diff
from
average
Highest for
December
2014
Mean for
December
2014
Diff
from
average
Lowest for
December
2014
Total for
December
2014
Average
for
December
Rank of
December
2014
Fraction of
December
average
Bickley 27.7 -0.4 38.0 30th 13.1 -0.6 8.9 17th 0.2 13.1 v low 2%
Garden Island HSF 24.9 -0.6 32.5 29th 16.7 -0.5 13.5 2nd 0.2 11.6 v low 2%
Gosnells City 29.9 -0.6 40.5 30th 15.7 -0.6 11.4 9th 0.1 11.4 low 1%
Jandakot Aero 29.0 -0.1 38.5 30th 14.0 -0.7 9.1 16th 0 10.5 lowest 0%
Pearce RAAF 31.1 +0.8 43.4 30th 13.9 -0.6 8.9 16th 0 10.4 lowest 0%
Perth Airport 29.7 +0.7 41.5 30th 14.9 0.0 10.4 14th 0.2 11.1 v low 2%
Perth Metro 28.9 -0.2 39.3 30th 15.8 -0.6 11.6 14th 0 13.3 lowest 0%
Rottnest Island 24.6 -0.5 31.3 27th 17.2 -0.4 13.8 10th 0 10.0 lowest 0%
Swanbourne 28.1 +0.1 38.8 19th 15.7 -0.8 11.9 14th 0.2 11.8 low 2%

Daily maximum temperatures for December 2014
12345678910111213141516171819202122232425262728293031
Bickley21.224.725.224.921.327.829.823.722.525.031.225.226.927.220.923.225.129.837.828.027.427.628.829.628.730.432.331.133.838.028.9
Garden Island HSF23.422.624.421.322.324.023.021.220.226.029.421.220.520.922.219.922.429.632.024.623.522.929.326.628.228.731.126.332.527.223.3
Gosnells City24.126.527.226.525.029.531.026.024.434.026.528.228.023.726.425.231.838.930.630.530.232.633.634.135.132.535.240.530.7
Jandakot Aero24.125.726.025.124.429.029.225.024.728.132.625.826.626.224.223.624.230.937.828.429.229.032.332.832.633.634.931.133.838.529.1
Medina Research Centre24.624.826.323.725.027.028.223.623.928.132.724.026.025.423.322.525.132.6
Pearce RAAF26.228.028.826.726.531.332.227.325.429.035.627.728.730.725.426.826.833.241.029.431.131.933.133.332.634.337.034.237.443.430.2
Perth Airport24.727.427.326.124.929.331.025.325.927.934.026.626.427.523.624.525.031.939.228.729.630.032.132.631.933.435.031.335.741.529.6
Perth Metro24.626.326.925.024.529.230.224.723.627.133.424.724.927.123.724.223.830.238.626.928.829.332.632.432.033.534.930.634.439.327.5
Rottnest Island23.722.823.523.022.923.824.622.921.524.229.422.921.421.822.921.321.626.230.723.623.623.626.925.225.726.431.324.726.331.124.0
Swanbourne24.326.325.324.126.126.026.625.122.627.432.924.423.323.824.423.123.430.838.825.827.527.034.431.833.333.433.528.134.837.026.0
Values are the maximum temperature, usually in the 24 hours from 9 am on the day indicated,
and typically occurred in the afternoon of that day.
Temperatures coloured according to their difference
from the long-term average for the period
-10.0 -9.0 -8.0 -7.0 -6.0 -5.0 -4.0 -3.0 -2.0 -1.0 0.0 +1.0 +2.0 +3.0 +4.0 +5.0 +6.0 +7.0 +8.0 +9.0 +10.0 °C Grey outline marks highest
and lowest for the period

Daily minimum temperatures for December 2014
12345678910111213141516171819202122232425262728293031
Bickley13.510.012.710.612.212.514.814.69.39.213.016.710.411.410.69.38.911.815.721.112.712.712.312.611.710.714.915.816.920.715.9
Garden Island HSF18.313.514.616.315.816.117.918.914.213.516.919.515.115.515.914.714.615.017.020.316.816.016.316.515.814.918.619.219.921.819.1
Gosnells City16.513.415.512.516.013.315.916.511.413.015.212.013.513.011.511.615.217.523.616.516.114.920.019.419.822.817.8
Jandakot Aero17.413.010.510.515.511.712.415.510.010.916.514.510.110.413.19.110.414.414.820.714.615.315.816.115.314.314.914.017.718.417.2
Medina Research Centre17.612.411.212.014.613.013.315.411.110.016.417.011.59.514.111.211.513.714.9
Pearce RAAF15.614.010.511.516.411.011.316.610.212.217.312.511.410.913.68.910.511.414.218.713.916.416.016.615.713.514.818.018.1
Perth Airport17.514.011.711.515.811.812.717.511.212.716.816.612.010.412.010.712.115.115.121.315.916.115.916.415.314.516.918.316.219.118.1
Perth Metro17.814.313.113.616.214.214.718.112.713.016.818.713.011.615.112.713.215.715.420.616.316.516.116.815.414.916.817.619.119.619.2
Rottnest Island17.714.217.116.916.517.818.818.015.013.816.918.815.416.316.815.215.716.318.819.616.817.216.617.316.615.818.719.519.420.618.8
Swanbourne17.413.714.114.216.014.815.518.112.212.016.718.912.511.914.912.112.614.416.320.315.016.416.117.015.914.819.017.218.619.819.5
Values are the minimum temperature, usually in the 24 hours to 9 am on the day indicated,
and typically occurred that morning.
Temperatures coloured according to their difference
from the long-term average for the period
-10.0 -9.0 -8.0 -7.0 -6.0 -5.0 -4.0 -3.0 -2.0 -1.0 0.0 +1.0 +2.0 +3.0 +4.0 +5.0 +6.0 +7.0 +8.0 +9.0 +10.0 °C Grey outline marks highest
and lowest for the period

Daily rainfall for December 2014
12345678910111213141516171819202122232425262728293031
Bickley - - - - - 0.2 - - - - - - - - - - - - - - - - - - - - - - - - -
Garden Island HSF - 0.2 - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Gosnells City - - - - - 0.1 - - - - - - - - - - - - - - - - - - - - - - - - -
Jandakot Aero - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Jarrahdale - 4.4 - - - 0.2 - - - - - - - - 0.2 - - - - - - - - - - - - - - - -
Medina Research Centre - - - - - 0.2 - - - - - - - - - - - - -











Mundaring - - - - 0.4

























Pearce RAAF - - - - - - - - - - - - - - - - - - - - - - - - -

- - - -
Perth Airport - - - - - 0.2 - - - - - - - - - - - - - - - - - - - - - - - - -
Perth Metro - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Roleystone - 0.5




























Rottnest Island - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Serpentine - 1.4 - - - 0.2 - - - - - - - - - - - - - - - - - - - - - - - - -
Swanbourne - - - - - 0.2 - - - - - - - - - - - - - - - - - - - - - - - - -
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 shown 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).
Rainfalls coloured
according to the amount
0 1.0 5.0 10.0 15.0 25.0 50.0 100 150 200 300 400 600 millimetres

Notes

A Monthly Climate Summary is prepared to list the main features of the weather in Perth 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.

A Climate Summary is generally published on the first working day of each month.

This statement has been prepared based on information available at 9 am on Tuesday 6 January 2015. Some checks have been made on the data, but it is possible that results will change as new information becomes available.

Averages for individual sites 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 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.

The ACORN-SAT dataset is used for temperature area averages.

Further information

Media
(03) 9669 4057
Enquiries