Following a succession of cold fronts across southern Australia, large areas of Victoria and New South Wales has recently experienced a succession of unusually cold nights for May. It appears that winter has arrived earlier than normal for 2021 as some of the minimum temperatures experienced are more likely to occur during June, July and into August than May.
The NASA Worldview image of Sunday May 16 2021 attached is showing extensive snow existing across the Snowy Mountains region of New South Wales. Similar snowfalls have also occurred across the higher regions of North East Victoria as a result of the recent cold fronts.
Frosts have been common and mornings have been cold. Minimum night time temperatures have also been colder than normal across Western Sydney.
A review of several weather stations across the state of New South Wales has identified the following minimum night time temperatures which have occurred between the 15 and the 21 May 2021.
1 - Albury Airport - 16 May 2021 - Minus 1.0C.
2 - Armidale - Overnight minimums have fallen between minus 0.7C and minus 5C between the 15 and the 21 May with the coldest minimum being minus 5 on the 16/5/2021. Armidale is elevated at 980 metres above sea level and much of the town sits within a valley where cold air pools at night and hence it can be colder in town than on the summit of nearby surrounding hills.
3 - Bathurst - The coldest morning occurred on the 19/5/21 where minus 4.5C occurred. It also fell to minus 4.1C on the morning of the 16/5 and minus 4C on the morning of the 18/5.
4 - Braidwood - 16 and 19 May 2021 - Minus 3.7C occurred.
5 - Cabramurra - 16 May 2021 - Minus 4.1C occurred.
6 - Cooma Airport - 18 May 2021 - Minus 6.4C occurred, 19 May - Minus 5.9C occurred and 20 May - Minus 5.3C occurred.
7 - Dubbo - 16 May 2021 - Minus 2.5C occurred.
8 - Glenn Innes Airport - 17 May 2021 - Minus 7.5C occurred.
9 - Goulburn - 19 May 2021 - Minus 5.1C occurred.
10 - Lithgow - 16 May 2021 - Minus 4.2C occurred.
11 - Oberon - 17 and 19 May 2021 - Minus 3.6C occurred.
12 - Orange - 16 May 2021 - Minus 4.0 occurred.
13 - Perisha Valley - 16 May 2021 - Minus 9.4C occurred.
14 - Tenterfield 17 May 2021 - Minus 5.2C occurred.
The coldest minimums have occurred at towns that are elevated but within valleys including Armidale, Bathurst and Lithgow.
Even in Western Sydney very light early morning front has been observed in the western areas of Blacktown around Doonside.
The plots attached to this post are taken from the Bureau of Meteorology Water and the Land and each show the minimum temperatures and temperature anomalies that have occurred during the period.