Greater Perth in July 2018: warmer temperatures

Rainfall in July 2018 was near average to above average across Greater Perth. Mean maximum temperatures were all above average. Mean minimum temperatures were more than one degree above average across Perth.

Near average to above average rainfall

  • Monthly rainfall totals were mostly in the 100-180 mm range, reaching 220-280 mm in the Perth hills
  • Daily rainfall of 1 mm or more was recorded on 17 or 18 days across Perth, including moderate falls on five occasions (3rd,5th,15th,22nd,25th); the highest daily rainfall was 55.6 mm at Karragullen North in the Perth hills on the 22nd

Above average mean maximum and minimum temperatures across Perth

  • Mean maximum temperatures were above average across Perth, with warm anomaly ranging from 0.4 °C at Bickley to 1.2 °C at Perth Airport
  • Mean minimum temperatures were 1 °C to 2 °C above average, but it was cooler than last July across Perth
  • The mildest mornings were on the 2nd or 3rd as the result of strong northerly to westerly winds and cloudy conditions; Rottnest Island had its highest minimum temperature in July on record on the 2nd

Perth Metro

  • Total rainfall for Perth Metro was 152.0 mm, which is near average
  • The mean maximum temperature for Perth Metro was 19.2 °C, which is 0.8 °C above average and the warmest July since 2012
  • Daily maximum temperatures ranged from 22.8 °C (highest) on the 10th to 16.0 °C (lowest) on the 5th, and the absence of very warm (above 25 °C) or cold (below 15 °C) days at Perth Metro
  • The mean minimum temperature for Perth Metro was 9.5 °C, which is 1.7 °C above average
  • The coldest morning was 4.1 °C on the 6th, and the warmest morning was 14.8 °C on the 2nd

Further information

Media
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Extremes in July 2018
Hottest day 23.3 °C at Swanbourne on the 10th
Warmest days on average 19.2 °C at Perth Metro
Coolest days on average 15.5 °C at Bickley
Coldest day 12.3 °C at Bickley on the 5th
Coldest night 2.6 °C at Jandakot Aero on the 6th
Coolest nights on average 8.3 °C at Bickley
Warmest nights on average 13.4 °C at Rottnest Island
Warmest night 17.4 °C at Rottnest Island on the 2nd
Warmest on average overall 16.0 °C at Rottnest Island
Coolest on average overall 11.9 °C at Bickley
Wettest overall 278.6 mm at Huntly
Driest overall 99.8 mm at Rottnest Island
Wettest day 55.6 mm at Karragullen North on the 22nd
Strongest wind gust 102 km/h at Rottnest Island on the 22nd

Record highest July daily minimum temperature
New record
(°C)
Old
record
Years of
record
Average for
July
Rottnest Island 17.4 on the 2nd 17.0 on the 27th in 1996 29 12.3



Summary statistics for July 2018
Maximum temperatures
(°C)
Minimum temperatures
(°C)
Rainfall
(millimetres)
Mean for
July
2018
Diff
from
average
Highest for
July
2018
Mean for
July
2018
Diff
from
average
Lowest for
July
2018
Total for
July
2018
Average
for
July
Rank of
July
2018
Fraction of
July
average
Bickley 15.5 +0.4 19.1 9th 8.3 +1.1 5.1 6th 271.8 218.3 high 125%
Garden Island HSF 18.5 +0.7 22.0 10th 12.3 +1.2 7.3 11th 120.0 115.5 average 104%
Jandakot Aero 18.8 +0.9 22.5 10th 8.8 +2.0 2.6 6th 195.0 174.0 average 112%
Mandurah 18.2 +0.8 21.8 10th 11.7 +1.1 7.3 6th 149.0 117.2 high 127%
Millendon (Swan Valley) 19.0   22.2 1st 9.0   3.3 6th  
Pearce RAAF 19.0 +1.1 22.8 1st 9.4 +1.0 3.3 11th 150.4 134.4 average 112%
Perth Airport 19.1 +1.2 22.5 10th 9.2 +1.2 3.0 6th 180.2 156.0 high 116%
Perth Metro 19.2 +0.8 22.8 10th 9.5 +1.7 4.1 6th 152.0 145.9 average 104%
Rottnest Island 18.6 +0.9 21.1 1st 13.4 +1.1 8.9 15th 99.8 112.6 average 89%
Swanbourne 19.1 +0.7 23.3 10th 11.3 +1.6 6.5 6th 172.8 150.3 average 115%

Daily maximum temperatures for July 2018
12345678910111213141516171819202122232425262728293031
Bickley18.816.014.814.312.315.613.316.319.118.718.017.115.812.413.614.514.614.514.717.015.514.415.415.416.817.212.714.215.815.815.6
Garden Island HSF20.920.118.118.015.816.917.219.819.522.017.720.019.018.317.918.018.418.517.519.319.517.817.719.319.318.016.617.518.916.718.2
Gosnells City22.018.519.517.820.222.021.319.118.016.518.818.521.219.720.020.520.517.017.619.7
Jandakot Aero22.019.418.618.615.316.719.921.222.519.420.619.018.016.817.918.218.317.920.118.418.518.418.920.319.316.617.519.617.618.8
Karnet19.417.314.812.616.019.020.115.914.314.815.415.418.016.016.813.516.6
Mandurah19.619.617.917.615.117.319.419.721.818.919.118.417.417.017.717.218.417.918.818.817.317.618.918.118.816.616.918.517.417.8
Millendon (Swan Valley)22.218.419.018.415.618.516.719.722.122.120.220.719.616.817.119.018.618.817.920.319.918.919.518.720.516.917.918.918.919.0
Pearce RAAF22.817.918.318.415.118.317.319.222.121.520.121.219.517.417.618.418.219.318.820.720.618.917.919.220.719.816.417.518.618.418.8
Perth Airport21.818.518.618.515.719.216.819.922.122.520.120.619.017.816.818.318.618.618.421.019.718.819.018.721.320.316.617.519.418.519.4
Perth Metro22.018.619.118.916.018.516.819.721.722.819.820.519.317.117.818.218.818.718.420.520.118.819.418.920.720.317.517.719.818.619.7
Rottnest Island21.119.918.218.016.616.716.319.719.820.119.320.518.918.818.318.617.818.317.119.719.918.018.519.419.118.717.217.619.217.618.3
Swanbourne21.819.218.818.116.118.417.120.320.823.318.421.319.117.918.018.318.719.418.319.719.018.419.418.320.318.817.519.818.119.1
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 July 2018
12345678910111213141516171819202122232425262728293031
Bickley6.012.311.18.76.05.17.95.25.36.97.37.910.07.95.99.47.611.07.05.910.011.210.010.29.79.110.47.69.09.55.2
Garden Island HSF12.615.816.214.410.17.511.110.79.88.67.38.813.211.89.513.915.215.310.310.614.315.114.314.214.313.614.311.912.014.39.5
Gosnells City8.012.512.55.56.97.88.67.08.510.86.07.0
Jandakot Aero4.914.214.412.98.52.65.35.93.94.63.73.210.96.97.210.59.112.66.85.313.014.113.010.710.29.012.89.710.311.93.4
Karnet9.911.07.82.77.04.03.66.99.15.86.34.311.812.010.26.56.9
Mandurah11.715.215.814.010.37.310.29.18.29.28.87.811.311.610.013.413.913.810.510.514.115.012.012.114.511.213.211.813.112.39.7
Millendon (Swan Valley)5.315.414.110.47.53.35.47.24.78.54.03.98.76.48.210.77.312.09.46.513.213.313.012.110.59.312.38.811.011.34.2
Pearce RAAF7.715.913.010.58.64.15.35.98.37.63.34.19.35.57.911.68.712.410.49.113.113.010.811.911.710.512.89.111.112.15.0
Perth Airport8.314.714.010.17.33.05.27.69.14.64.23.59.87.18.110.68.313.07.48.113.414.014.012.110.59.212.79.210.312.44.7
Perth Metro6.314.814.712.99.14.15.85.74.94.65.05.210.68.28.810.58.814.67.76.412.314.014.312.411.49.713.010.011.412.84.8
Rottnest Island13.717.415.913.310.511.012.611.911.613.114.014.514.214.58.914.014.214.812.313.415.314.211.014.015.212.813.413.313.714.012.5
Swanbourne9.515.715.713.810.16.58.88.08.47.88.87.311.99.99.312.314.415.59.49.113.314.514.213.212.812.912.911.012.512.77.5
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 July 2018
12345678910111213141516171819202122232425262728293031
Anketell - 2.2 41.0 7.8 18.0 2.6 - - - - - - 7.4 0.6 13.4 5.0 2.2 0.4 4.8 - 5.0 23.0 8.0 1.4 4.0 30.4 2.4 4.2 - 8.6 -
Bickley - 3.6 45.6 6.4 29.8 0.4 0.2 0.2 - - 0.2 - 12.4 2.4 23.6 12.0 3.6 - 5.8 0.2 9.2 50.8 8.2 8.2 1.2 36.6 3.4 3.4 0.2 4.2 -
Bungendore - 5.2 44.0 9.2 22.0 0.4 0.4 - - 0.4 - 0.4 11.8 0.8 21.8 9.8 3.2 0.8 2.8 - 6.6 28.8 10.6 1.8 1.6 31.8 1.4 3.0 - 8.6 0.4
Chidlow 4.6 33.8 - 28.8 0.4 - - - - - - 3.8 0.4 27.2 2.8 - 1.8 - 2.8 32.8 9.2 1.4 30.8 1.4 1.4 1.8
Garden Island HSF - 3.8 33.4 2.6 9.4 0.8 - - - - - - 3.2 0.2 16.0 1.2 1.2 - 3.0 - 4.6 5.4 3.0 2.4 2.8 16.2 3.8 3.4 - 3.6 -
Gidgegannup - 0.6 34.0 2.8 25.6 0.6 - 0.2 0.2 - - - 4.0 0.6 23.8 7.0 3.4 0.2 4.0 - 5.6 24.2 8.4 14.8 1.4 28.6 1.0 2.6 - 2.4 -
Gosnells City - - - - - - - - - - 11.4 1.0 21.3 6.0 5.6 - 4.6
Hopelands - 38.8 25.0 17.0 1.0 - - - 3.6 1.0 13.0 5.4 0.8 1.4 0.8 - 15.4 7.6 2.6 1.8 4.0 25.8 0.8 2.0 5.2 0.2
Huntly - 2.8 39.4 13.2 24.8 0.8 - - - - - - 2.0 1.8 23.4 13.8 3.2 3.6 4.8 - 3.2 37.0 6.8 4.4 35.0 47.8 1.4 2.2 - 7.2 -
Jandakot Aero - 4.2 33.2 2.4 12.0 1.8
-
- - - 7.6 0.4 17.4 4.0 3.0 0.8 5.8 - 10.8 28.0 5.6 1.8 2.6 37.4 2.4 6.2 - 7.6 -
Jarrahdale - 2.6 42.6 5.6 26.2 0.4 0.2 0.2 0.2 0.2 0.4 0.2 10.4 0.8 18.4 11.2 4.4 2.0 5.0 0.4 4.4 30.8 7.4 2.8 2.4 43.8 1.4 2.0 - 7.0 0.2
Karnet 4.7 30.0 43.6 0.9 1.5 - - - 0.1

2.0 20.1 3.6 1.6 - 8.0 34.1 8.2 1.6 15.0
Karragullen North - 4.4 33.2 11.4 19.2 0.4 - - - - - - 13.4 - 24.2 13.4 8.6 1.0 6.4 - 8.2 55.6 9.2 6.2 0.8 30.8 1.8 3.8 - 5.4
Maida Vale - 3.2 33.6 4.4 12.6 1.4 0.2 - - - 0.2 - 9.2 0.8 17.4 6.4 0.8 - - - 7.8 30.8 3.2 7.0 0.6 26.4 3.4 3.4 - 5.6
Mandurah - 9.0 25.4 4.0 11.8 1.6
- - - - - 3.0 6.8 8.0 1.8 0.6 0.6 2.2 - - 4.0 6.0 2.0 15.8 34.0 1.8 2.2 0.2 8.0 0.2
Midland 1.0 - 25.1 17.8 0.8 - - - - - - 34.2 - 2.4 - 30.6 - 7.2 17.8 3.2 4.8 -
Millendon (Swan Valley) - 0.6 24.6 1.6 16.0 0.8 - - - - - - 4.8 1.0 14.4 4.0 2.8 - 2.0 0.2 3.8 16.4 4.6 7.4 0.4
4.0 1.6 0.2 1.6 0.2
Mosman Park 20.0 0.6 6.4 11.0 3.4 - - - - - - - - - 30.1 0.8 - 2.3 - - - 45.8 - 4.4 31.0 3.4 10.2 0.2
Mount Solus - 4.8 50.2 21.4 35.6 0.2 0.2 0.2 0.2 - - - 7.4 0.8 15.4 13.6 1.6 2.2 2.6 - 3.4 31.2 19.0 2.8 3.8 30.0 0.8 2.0 - 4.0 -
Muchea - 1.0 37.8 1.4 15.8 2.2 0.2 - 0.2 - - 0.2 2.0 0.6 14.6 2.4 1.4 - 2.2 - 2.4 14.8 3.8 4.4 1.6 23.2 3.4 2.8 - 1.2 -
Mundaring - 1.6 32.0 2.8 28.8 1.4 - - - - - - 8.6 - 26.4 14.0 5.4 0.2 3.2 0.2 6.0 32.8 7.8 9.6 2.0 24.4 4.2 2.2 - 4.6 0.2
Noble Falls
1.2 41.0
30.0




5.0
3.4
18.0
4.6
2.0
3.0 18.0 6.6 10.0 2.0 30.0 1.0 2.0
2.0
Pearce RAAF - 0.6 33.8 0.8 23.8 0.4 - - - - - - 3.4 0.2 17.2 2.0 1.2 - 2.0 - 1.8 13.8 8.6 7.2 1.6 22.6 2.8 3.2 - 3.4 -
Perth Airport - 2.2 26.6 3.6 18.0 0.6 - - - - - - 10.8 0.4 24.0 8.8 1.8 - 1.0 - 3.0 35.6 2.6 5.8 0.2 23.2 2.6 5.0 - 4.4 -
Perth Metro - 3.4 31.2 2.8 10.8 1.4 - - - - - - 8.6 0.8 23.4 6.2 1.2 - 2.0 - 5.2 20.2 2.0 5.4 0.6 17.4 3.0 4.8 - 1.6 -
Pinjarra Refinery - 6.0 26.4 10.4 15.2 0.8 - - - - - - 6.6 0.8 14.4 4.6 1.7 1.8 0.8 - 6.0 16.0 3.0 1.8 4.4 23.2 1.3 0.8 - 5.2 0.2
Pinjarra South - 5.8 28.0 13.6 17.2 0.6 - - - - - - 4.0 1.8 11.4 4.2 1.0 0.8 0.8 - 2.0 12.2 1.8 2.2 5.2 23.4 1.0 1.8 - 9.2 -
Roleystone - 4.4 27.6 15.8 19.8 - - - - - - - 8.4 1.4 16.4 10.4 4.0 0.6 6.8 - 6.6 46.0 6.4 3.6 1.6 30.6 2.8 2.4 - 5.0
Rottnest Island - 4.2 25.4 5.2 3.2 3.2 - - - - - - 1.0 - 8.0 2.8 0.6 - 2.0 - 1.2 12.4 2.2 0.2 9.0 11.6 4.2 0.8 - 2.6 -
Serpentine - 2.4 37.8 5.4 17.2 0.2 - - - - - - 5.2 1.0 13.4 5.2 1.2 0.8 1.2 - 2.2 14.4 5.0 3.0 4.0 30.4 1.6 2.2 - 8.2 -
Swanbourne - 5.8 21.2 4.0 11.0 3.4 0.2 - - - - - 5.2 0.6 21.2 4.6 0.8 - 2.6 - 6.2 36.8 2.8 5.0 1.0 31.0 5.6
- 3.8 -
Wanneroo 3.6 24.2 18.2 1.6 - - - - - - 4.4 15.0 1.2 0.4 3.4 - 38.6 2.0 17.2 5.0 10.5
Werribee 0.2 0.8 37.6 0.8 28.2 0.2 0.2 - 0.2 - - 0.2 1.8 0.2 15.6 3.0 2.2 - 1.4 - 1.6 13.8 9.4 9.6 0.2 25.8 1.0 1.8 - 1.8 -
Whiteman Park - 2.0 26.0 2.2 20.0 - - - - - - 1.2 6.8 1.2 14.6 5.6 - 3.2 - - - 3.6 3.2 - 9.4 22.0 3.0 3.2 - 2.0
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

The Monthly climate summary, generally published on the first working day of each month, lists the main features of the weather in Greater Perth using the most timely and accurate information available on the date of publication; it will generally not be updated. More extensive discussion of significant weather events, along with later information and data that has had greater opportunity for quality control, will be presented in the Monthly Weather Review.

In September 2017 this summary was broadened to include data from observing sites in or near the Greater Perth “Greater Capital City Statistical Area” (GCCSA). The Australian Bureau of Statistics designed the GCCSAs to “include the population within the urban area of the city, as well as people who regularly socialise, shop or work within the city, and live in small towns and rural areas surrounding the city. It is important to note that GCCSAs do not define the built up edge of the city. They provide a stable definition for these cities and are designed for the output of a range of social and economic survey data.

This statement has been prepared based on information available at 9 am on Wednesday 1 August 2018. Some checks have been made on the data, but it is possible that results will change as new information becomes available.

In some situations, some or all of the rainfall is in the form of hail or snow. In these cases the totals given are for the water equivalent: the depth of liquid water that results from melting any frozen precipitation. There can be significant 'undercatch' of snow in strong winds, meaning the true precipitation can be higher than that reported.

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.

Where temperature area averages are mentioned, they are derived from the ACORN-SAT dataset.

Further information

Media
(03) 9669 4057
Enquiries