The Bureau of Meteorology released its Annual Climate Statement this morning, which revealed 2018 was the warmest on record for NSW for both mean temperature and mean maximum temperature, while the mean minimum temperature was fourth-warmest on record.

The year was dominated by very dry conditions, with the third-driest January to September on record. October to December saw some relief from the dry, with above average rainfall across parts of the State. Despite this, NSW experienced its sixth-lowest annual rainfall on record; its driest year since 2002.

The Australian annual climate statement provides a comprehensive summary of Australia's climate during 2018. Information about changes and long-term trends in Australia's climate can be found in State of the Climate 2018.

A very dry year for NSW as a whole; 40 per cent below average, the sixth-driest year on record and the driest since 2002.

It was particularly dry during autumn and winter with May rainfall eighth-lowest on record, and July fifth-lowest.

October and November were the only months of 2018 where the State's total rainfall was above the monthly average.

In October, the heaviest rainfall was focused along the northern two thirds of the east coast, while November was mostly in the south and central regions.

Despite the low total rainfall, surface troughs and low pressure systems resulted in locally heavy falls throughout the year and a few sites even had their wettest day on record.

Below average rainfall for the year resulted in more than two-thirds of the State ranking in the driest 10 per cent of historical observations and multiple sites had their lowest total rainfall on record.

2018 was the warmest on record for New South Wales, with a mean temperature 1.68 degrees above average (the previous record anomaly of 1.50 degrees was observed in both 2017 and 2014).

Many individual sites across the state experienced their highest annual mean temperature on record.

The state's mean maximum temperature was also highest on record, 2.13 degrees above average and well above the previous record of 1.92 degrees in 2017.

Many areas had their highest annual mean daily maximum temperature on record.

Above average monthly mean maximum temperatures have persisted over the past two years; April 2017 was the last time the state as a whole experienced a cooler than average month.

Minimum temperatures for the year overall were very warm, with the 2018 mean minimum temperature for the state fourth-warmest on record and 1.23 degrees above average.

Extreme heat featured throughout 2018, and especially so in January, April and December.

January, the fifth-warmest on record for NSW saw record high daily temperatures across the Sydney region.

April was record warm (as detailed in the Special Climate Statement Persistent summer-like heat sets many April records) and saw a monthly mean maximum temperature anomaly of 4.45  degrees.

The New South Wales mean minimum temperature for December was the highest on record, including record warm nights at Hume and Griffith.

While the months from May to September experienced near-average nights for the State as a whole, some clear nights during the winter months brought cooler than average night time temperatures and numerous areas had their lowest temperature on record.