According to www.weatherzone.com.au, which uses Bureau of Meteorology data, the mercury will plunge to an icy -6 degrees in the early hours of Sunday morning.

If the mercury gets that low it will be the city’s coldest mark of 2018, eclipsing the -5.1 degrees registered on June 24.

The forecast for the days before and after Sunday isn’t much better, with minimum temperatures of -4 and -5 degrees predicted for Saturday and Monday respectively.

The weekend’s forecast maximums will be restricted to single digits, with tops of 8 degrees (Saturday) and 9 degrees (Sunday) on the radar.

Sadly, there’s no meaningful rain in the week-long forecast, with less than one millimetre tipped to follow heavy frosts on each of the next seven days.

According to weatherzone.com.au’s Ben Domensino, the string of dry days and frosty nights is the result of a high pressure system which is drifting across NSW.

Despite light showers falling in pockets of southern and eastern NSW on Wednesday and Thursday, most of the state's parched inland districts are having yet another dry week.

The only rain registered this month at Orange Regional Airport – where weatherzone.com.au makes its readings was the 0.2 millimteres on both July 1 and 12.

Meanwhile, Dubbo's July total is 0.6 millimetres, while Tamworth has only collected 0.8 millimetres, which follows their driest June in 18 years.

Many areas of far western NSW haven't received any rain so far this month, including Broken Hill, which just registered its driest first half of a year on record.

Mr Domensino said the high pressure system passing over NSW will keep any significant rain-bearing systems at bay during the remainder of this week.

In addition to the dry weather, the clear skies will cause the cold and frosty mornings.