Tuesday, 1 September 2020 - Seasonal Climate Summary for New South Wales - Product code IDCKGC25R0

New South Wales in winter 2020: a season of two halves

Winter 2020 in New South Wales had two contrasting halves. A warm and dry start made way to a succession of cold fronts bringing cool conditions and heavy rain to much of the state. Overall, it was the wettest winter, with the coolest days, since 2016.

Dry, then wet

• Winter 2020 started with below average rain in June, the fourth such June in a row.
• From mid-July a series of complex low pressure systems brought heavy rain, flooding and high seas along the coast.
• During 13–14 July a low pressure system created a powerful sea swell, with wave heights of 5 to 6 m leading to significant coastal erosion, most notably at Wamberal.
• Three low pressure systems each brought over 100 mm of rain to the South Coast region from mid-July to early August.
• The highest rainfall totals over the South Coast occurred during 8–10 August, with up to 370 mm at some sites over the three days and flooding of the Moruya and Shoalhaven rivers.
• Some sites had their highest winter daily rainfall on record.
• Several sites had their highest total winter rainfall on record, exceeding winter 2016, or their highest total winter rainfall since 1998.
• Overall, New South Wales winter rainfall was around 5% above the historical average, the wettest since 2016.
• New South Wales has already received more rainfall in January to August 2020 than it did in either 2018 or 2019 as a whole, with statewide year-to-date rainfall currently 14% above average.

Warm, then cool, days

• Mean daytime temperatures were above average across the state in June and July, although cooler than in recent winters.
• A succession of cold fronts during August meant that daytime temperatures were the coolest for August since 2010, and two sites had their coldest winter day on record.
• For the state as a whole, winter mean daytime temperatures were 0.58 °C above average, the coolest since 2016.
• Clear skies and drier conditions resulted in below average mean minimum temperatures in the south-west of the state.
• In contrast, cloudy conditions along the coast meant that mean minimum temperatures were generally above average.
• Overall, the wet and cloudy conditions meant that mean minimum temperatures were 0.59 °C above average, the warmest since 2016.
• The year-to-date (January to August 2020) mean temperature for the state is 0.55 °C above the historical average.

Winter snow

• A series of cold fronts during 13–14 July and 21–23 August brought substantial snow to alpine regions.
• Snow depths in winter 2020 at the Snowy Hydro Spencers Creek snow course have generally been around 50 to 75% of those reported for the same time in 2019.
• Snow fell across parts of New South Wales several times during August, including heavier falls across the ACT, New England and towns in the Blue Mountains on the 22nd.

Extremes Maps Records Summaries Important notes the top

Extremes Maps Records Summaries Important notes the top

Maps
	Observed	Anomaly	Decile rank
Total rainfall
Mean daily maximum temperatures
Mean daily minimum temperatures

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* note: there are gaps in the historical record at this site, so it is possible a higher value has gone unreported

* note: there are gaps in the historical record at this site, so it is possible a higher value has gone unreported

Extremes Maps Records Summaries Important notes the top

Extremes Maps Records Summaries Important notes the top