Meteorologist with weatherzone Tom Hough said wave heights for Monday were around one metre.

"However, the conditions are much bigger out to sea with two to three metre swells," he said.

"It looks like it will be fairly similar conditions into Tuesday as well.

"We are expecting these conditions to increase overnight on Tuesday before peaking to three and possibly four metres on the coastline on Wednesday afternoon.

"People on or near the coastline or out to sea should take the necessary precautions and keep up to date with any warnings issued at the time.

"There is a current surf warning for the Macquarie coast which is in effect for today."

The hazardous surf warning - issued by the Bureau of Meteorology - covers the Macquarie, Hunter, Bryon and Coffs coasts.

Surf and swell conditions are expected to be hazardous for coastal activities such as rock fishing, boating, and swimming. 

The dominant swell is currently from the south.

Mr Hough said the weather forecast was fairly consistent through this week with minimum temperatures down to around eight degrees expected for Tuesday.

"Tuesday's maximum temperature is forecast for 21 degrees, with really clear conditions," he said.

"From Wednesday to Friday, the maximum temperatures will remain around 21 or 22 degrees but there is likely to be some more cloud which will see minimum temperatures climb to 10 or 11 degrees for the same period.

"The weekend looks likely to be pretty similar with 20 degree maximums and nine degree minimums."

The meteorologist said a high pressure system remained in place over the Great Australian Bite which was bringing clear, sunny conditions.

This system will slowly move in an easterly direction on Thursday afternoon or evening as a cold front starts to move onto the Western Australian coastline.

Winds on the Macquarie coast will remain consistent at around 15 kilometres per hour through to Wednesday before easing.