Accumulated rainfall totals for NSW from the GFS Model.
Accumulated rainfall totals for NSW from the GFS Model.

200mm of rain, ‘significant uncertainty’ over weather

Rain is setting in across the Northern Rivers, with some weather experts predicting up to 200mm could fall over the next few days.

According to EWN Alerts NSW, there are wet conditions ahead across the next week for the coastal strip, particularly in the northeast of the state.

"A high over the Tasman Sea directs an unstable south-easterly flow over the region," they posted on Facebook.

"Some models indicate the possibility of a low pressure system having some effects over the northeast of the state around the weekend, however there is significant uncertainty around this system at this stage.

"Widespread falls of 50-100mm are expected over the next five to six days … with some areas seeing 100-200mm and isolated higher totals expected.

"Falls will be lighter the further south you go."

The Bureau of Meteorology confirmed a low pressure trough was situated off the NSW coast while a high pressure system was to the southeast of Tasmania.

"This pattern is directing mild and mainly dry air across inland parts, and showers along the coast," they posted online.

"Showery conditions are likely to persist throughout the week in the east, as the high pressure system slowly drifts eastwards across the southern Tasman Sea, maintaining an onshore flow."

Thunderstorms are expected to develop in the region by Friday.