The highest expected temperature tomorrow is 27, which is eight degrees lower than today's max.

Today's maximum is the highest the mercury will climb over the next seven days, according to the forecast.

The chance of rain tomorrow is 80 per cent.

There is a similar chance of showers Thursday when the Bureau of Meteorology forecasts a high (80 per cent) chance of rain.

The UV index is predicted to be 11. There is an extreme risk of harm from sun exposure. Unprotected skin can burn within minutes in today's conditions. Experts suggest looking for shade and avoiding sun exposure around noon. General advice is to take all precautions such as using eye protection, sunscreen and covering up.

Winds will be south-southwest around 12 km/h in the morning shifting to east-southeast around 16 km/h in the afternoon.

Details for the next six days:

Wednesday, December 10: Mostly cloudy. SW/SE winds Min - 18. Max - 27.

Thursday, December 11: Mostly cloudy. Showers. S'ly winds Min - 17. Max - 21.

Friday, December 12: Mostly cloudy. Showers, heavy at times. S/E'ly winds Min - 17. Max - 21.

Saturday, December 13: Morning fog patches. Late shower. NW winds tending NE Min - 16. Max - 31.

Sunday, December 14: Morning fog patches. Mostly sunny afternoon. NW winds tending NE Min - 18. Max - 32.

Monday, December 15: Mostly cloudy. Showers. Fresh SW/SE winds Min - 17. Max - 26.

The previous Parramatta weather article can be viewed here.