THE Tweed copped more than the entire average rainfall for August in just 24 hours, with a heavy deluge blanketing the region since late yesterday.

Heavy falls have been recorded across the Northern Rivers, with Murwillumbah registering 58mm overnight.

Weatherzone meteorologist Kim Westcott said Murwillumbah was one of the state's wettest areas overnight, with the 58mm of rainfall recorded before 9am this morning.

While Tweed heads and Coolangatta were slightly drier overnight, some 26mm fell before 9am, followed by heavy rain today.

"Since 9am this morning, we've picked up an additional 29mm on top of the 26mm,” Ms Westcott said.

"To put that into context, the average for August is around 61-62 mm for the whole month.

"In the past two days we've already exceeded that August rainfall average - and that's not including what's fallen since 9am - which (takes the total to) 83.2mm.”

In comparison, Lismore picked up a whopping 74mm overnight and around 19mm since 9am.

Ms Westcott said rain would continue into this evening, before conditions returned to normal on Thursday.

"We are looking at an easing trend but it may not be until closer towards tonight,” Ms Westcott said.

"So we've still got quite a few hours of rain, but once the low moves offshore, we should see a substantially drier day on Thursday.”

Despite the heavy rainfall, no flood warnings have been issued for the Tweed River.

Ms Westcott said while it should be sunny and dry from tomorrow, temperature highs should decrease from 24 degrees , to a cooler 22 degrees into Friday, with tops of 20 degrees expected for the weekend.

• Information on how residents can prepare for severe weather can be obtained by visiting the NSW SES website www.ses.nsw.gov.au.
• For emergency assistance in storms and floods call the NSW SES on 132 500 and in life threatening situations call triple zero.