There is stormy weather on the horizon for Sydney with commuters warned to prepare for a slow and soggy trip home on Thursday evening.

Severe thunderstorms have been developing in the western part of NSW, moving east towards the coast and expected to hit Sydney in the late afternoon or early evening.

Weatherzone senior meteorologist Graeme Brittain​ has warned Sydney residents to prepare for a soaking.

"There will be storms across the eastern part of NSW this afternoon," he said.