Residents have been sweating through the hottest run of days since January this year, according to The Weather Channel at Foxtel’s Dick Whitaker.

He said a low pressure trough will move across NSW from South Australia, bringing with it hot northerly winds.

“Then the trough [will be] moving across the area giving us a lot more cloud cover around on Saturday,” the chief meteorologist said.

Tomorrow should hit 34 degrees, with a cooler day of 29 expected on Sunday.

The Bureau of Meteorology predicted an overnight low of 18, with the mercury only dropping to 20 tonight.

The state’s health department said while heat-related illness may affect anyone, certain groups are particularly vulnerable.

During a heat wave, it is very important to stay in regular contact with your elderly friends, neighbours and relatives, and to look out for other vulnerable members of your community.

“Heat puts a lot of strain on the body and can cause dehydration, heat exhaustion and heat stroke,” Dr Richard Broome, NSW Health Medical Adviser in Environmental Health said.

“It can also make underlying health conditions worse. However, being prepared and taking some simple precautions can reduce the risk of heat-related illness.”

The Rural Fire Service is warning people to be careful, with the entire summer tipped to be a hot one.

“People just need to be extra vigilant this weekend,” Peter Alley from Yass fire control centre said.

He warned the lighting of any sort of fire wasn’t permitted this time of year.

High fire danger is expected for the weekend and any permits issued would be cancelled under those circumstances.

“People need to be very careful mowing lawns and whipper snipping. If they need to undertake those activities, it’s best to do it before seven o’clock in the morning or late [at night].”

The firies will be standing by the phones but hoping they won’t need to take action.

Today: 37

Tomorrow: 34