Wednesday, 6 January 2016 - Annual Climate Summary for Perth - Product code IDCKGC51L0

Perth in 2015: a very warm year with dry winter and spring

All sites in the Perth metropolitan area recorded above average annual mean maximum temperatures for 2015, with Perth Metro recording its equal warmest year on record. Annual mean minimum temperatures were also above average across Perth. 2015 was a dry year in the Perth area as a result of below average rainfall in winter and spring.

• Mean maximum temperatures above average for all sites; equal highest at Perth Metro with 2011 and 2012
• Mean minimum temperatures above average for all sites
• Rainfall below average for most sites, generally by at least 150 mm
• Highest number of days over 20 °C in June at Perth Metro
• Ninth-driest winter on record at Perth Metro
• Earliest occurrence of 32 °C in September at Perth Metro
• Warmest October on record at most sites, including Perth Metro which broke the previous mean maximum temperature record for October by 1.0 °C

Mean annual maximum temperatures in 2015 ranged from around 23 °C on the islands and in the hills to about 25 °C or 26 °C across much of the coastal plain, and were generally between 1 °C and 2 °C above average. Perth Metro recorded its equal warmest year in 117 years of record, equal with 2011 and 2012. Apart from a relatively cool autumn, most months experienced warmer than normal daytime temperatures, with record warm days observed in June, September and October for most sites.

Mean annual minimum temperatures in 2015 were also above average. They were about 16 °C on the islands, about 14 °C near the coast, and between 12 °C and 13 °C on the coastal plain and in the hills. Apart from cooler than normal nights in autumn, most months saw minimum temperatures that were average or above, with warmest on record nights observed in October at most sites.

Annual rainfall for 2015 were below average for most sites, with totals ranging from about 500 mm on the islands and in the far northeast of the metropolitan area, to between 600 mm and 700 mm on much of the coastal plain, and to about 900 mm in the hills. Monthly rainfall totals were generally at or below average in most months, with only February and December seeing above average rainfall. However, winter was noticeably dry, with Perth Metro observing its ninth-driest winter on record.

Extremes Records Summaries Important notes the top

Notable events in 2015

• 5 January: the hottest day in 2015 across the Perth area with daily maximum temperatures in the low to mid-forties. A temperature of 44.4 °C at Perth Metro was the third-highest January temperature in its 119 years of record
• 29 January: a deep trough near the west coast triggered widespread thunderstorms in Perth. Hail up to 3 cm in diameter was reported in the suburb of Thornlie, and approximately three thousand homes lost power
• 1-3 February: Perth Airport recorded thunderstorms on 3 consecutive days, equalling the highest number of consecutive thunderstorm days on record on 17-19 February 1978
• 7-13 April: The Perth area saw seven consecutive rain days due to a slow moving low pressure system and persistent cloudbands, which was the longest wet spell in April at Perth Metro for 35 years
• May: Perth Metro only reported 4 rain days, equalling the lowest number of rain days on record (May 2009)
• June: Perth Metro recorded 21 days with daily maximum temperatures above 20 °C, equalling the highest number of such days on record (June 1983)
• 9 September: Perth Metro recorded a maximum temperature of 32.1 °C, which is the earliest occurrence of 32 °C in September at Perth Metro, overtaking the previous early-season record (32.3 °C on 18 September 1988)
• October: unprecedented warmth across the Perth area. The mean maximum temperature of 26.8 °C at Perth Metro was 1.0 °C higher than the previous record in October 1969. Daily maximum temperatures were above 30 °C for 8 days at Perth Metro, exceeding the previous record of 6 days in October 2008

Extremes Records Summaries Important notes the top

Extremes Records Summaries Important notes the top

Extremes Records Summaries Important notes the top

Extremes Records Summaries Important notes the top

Extremes Records Summaries Important notes the top