Wild weather conditions are predicted to lash parts of New South Wales on Sunday afternoon, with conditions in Victoria expected to remain icy as the state is swept by another cold front.

The Bureau of Meteorology forecast weather conditions in NSW would ease on Sunday morning before picking up again with strong and gusty winds in many areas of the state for the rest of the day.

Areas including Newcastle, Woollongong, Nowra, Armidale, Katoomba, Grafton and Goulburn were forecast to be affected.

A strong wind warning was in place for Sunday for Sydney’s closed waters and the Byron and Coffs coast with gale warnings for the Macquarie, Hunter, Sydney, Illawarra, Batemans and Eden coast.

Hazardous surf was also predicted for these regions along with the Coffs coast.

The vigorous westerly to south-westerly winds would be beneficial in one respect – providing a tailwind for about 75,000 runners and walkers participating in Sydney’s City2Surf fun run on Sunday.

The bureau said the last of a series of cold fronts sweeping across the state would clear on early Monday.

The NSW SES had received some 1,167 requests for help by 6pm on Saturday since the weather event began, with a lot of these spread over the south-eastern half of the state especially the Blue Mountains.

NSW SES volunteers responding to a request for assistance at south Coogee in Sydney at midnight on Friday night. Photograph: NSW SES

SES members worked with police and the Rural Fire Service in this area to prepare for snow overnight on Saturday and into Sunday, a NSW SES spokeswoman said.

Teams in 4WD’s were patrolling the Great Western Highway with first aid and emergency supplies and set up refuge stations along the highway.

In Victoria, early Sunday morning snow flurries surprised and delighted Victorians but it came with warnings of “treacherous” conditions in the alpine regions.

Thick snow was spotted at Daylesford, Hepburn, Woodend, Creswick, the Dandenong Ranges and Mt Macedon.

“There have been snowfalls at fairly low levels, which is a little more unusual,” Bureau of Meteorology senior forecaster Dean Steward said on Sunday.

Areas as low as 400m had gotten snow dumps overnight and into Sunday morning. “There’s been a good layer of snow around,” he said.

The falls came as road closures and weather warnings remained in places across parts of the state.

Conditions in the alpine areas were labelled “treacherous” by VicRoads.

“Heavy snow falls and freezing temperatures have resulted in road closures and treacherous driving conditions in our Alpine areas. With little wind, snow-laden trees are falling, blocking access,” a statement read.

Popular alpine resort Mount Baw Baw was shut off, with the closures on Mount Baw Baw Tourist Road and South Face Road.

Dangerous black ice was also detected on parts of the Calder Freeway and Macedon-Woodend Road.

“If you’re heading to mountainous areas, please drive with extreme care as you may encounter snow or black ice,” VicRoads warned.

On Sunday a four-year-old Melbourne boy remained in a critical condition after a tree crashed on to his family’s car amid winds of more than 100km/h on Friday. His mother, named by media as Angie Suryadi, died when the tree came down on the car at Fernshaw, as storms lashed the state.

Oliver, four, was taken to the Royal Children’s hospital in a critical condition, and was understood to be in an induced coma. His five-year-old brother, Johnathon, was also taken to hospital before being discharged on Saturday.

Their father, 41-year-old Arnold Adiatiasvara, remained at the Alfred hospital in a stable condition.

“The whole family are just [a] beautiful family,” Lifo Wijaya, from the family’s Australia for Christ Church at Rowville, told Nine News on Saturday. “We believe in miracles so we really appreciate people praying for this family.”

Hundreds of people called the State Emergency Service for help during Friday’s storms, mostly for fallen trees, as the damaging cold front swept the state.

Rough seas also swept away part of Frankston’s pier in Melbourne’s south-east before it washed up on a nearby beach.

Winds eased on Saturday but conditions remained gusty across much of the state, with the SES receiving 166 calls for help in 24 hours. Wilsons Promontory recorded winds of 119km/h, Gabo Island 98km/h and Port Phillip Bay 83km/h.

On Sunday as another cold front moved across Victoria, Melbourne was forecast to reach a top of just 12C, with maximum temperatures over alpine as low as -3C.