Parts of western NSW shivered through their coldest morning in nearly 20 years on Friday.

Dry and cold air, combined with clear skies and light winds, sent the mercury plummeting across NSW on Friday morning.

Image: Projected surface temperatures on Friday morning according to the ACCESS-R model.

Narrabri hit a low of -4.6 degrees, its coldest morning for any month in 17 years.

Bourke (-3.4C), Moree (-2C) and Tibooburra (1.3C) registered its lowest temperatures in nine, eight and seven years respectively.

Cobar had its coldest June morning in 17 years for the second day in a row, with Friday's -4.7 degrees trumping Thursday's -4.4 degrees.

Sydney only dropped to a low of 7.5 degrees on Friday morning, although the apparent temperature was -0.9 degrees at 8am due to a combination of wind and the air being so dry.

Morning frosts will continue to be widespread in NSW this weekend.