Storms will dump up to 80mm of rain across NSW today and another 100mm is forecast for tomorrow.

The NSW Hunter region and mid-north coast are set for the state's heaviest rainfall today, with conditions easing somewhat in Sydney and the southeast.

Weatherzone senior meteorologist Brett Dutschke said at least 40-80mm will fall in the mid-northeast today, with 100mm on the cards for the start of the weekend.

A flood rages outside a Wollongong resident's home. (Facebook)

Severe wind warnings are in place for the Hunter, which will see a similar amount of rain, and will probably extend north later today as well.

Sydney, the South Coast and the Southern Highlands will get some respite today after a week of torrential rain that have led to dangerous floods in the south.

However, the regions will be buffeted by high winds which could hamper clean-up efforts. Heavy surf is also expected along the coast.