The Bureau of Meteorology has forecast a 50 per cent chance of showers in Wollongong during the afternoon and evening, but even if they occur the city's gardens cannot hope for much of a drink, with less than 1 millimetre of rain expected. 

Wollongong, Sydney and NSW recorded their driest Septembers on record. No rain fell at Albion Park during September, with just 0.4mm recorded at Bellambi. 

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The last rain that fell at Bellambi was 0.4mm on September 17 and before that 2.8mm in late August. 

At Albion Park, 0.2mm was recorded on Friday. Prior to that, the most-recent rainy day was August 28 (when 1.2mm fell).

"It's not looking hugely promising," the Bureau of Meteorology's Gabrielle Woodhouse said of Sydney and Wollongong's rain outlook. 

The meteorologist said thunderstorms in the state's west were not likely to bring more than "a couple of drops" past the foothills of the Blue Mountains.  

"We really haven't had any rainfall effectively from early August."

While the bureau forecasts a series of possible showers on Monday, Thursday and Friday, only Saturday's expected rainfall band extends above 2mm (1 to 3mm). 

Wollongong on Sunday faced a maximum temperature of 23 degrees, with light winds becoming north to northeasterly in the middle of the day.

On Monday, the temperature is set to hit 28 degrees on the coast and 29 inland, with a 50 per cent chance of afternoon showers and the possibility of an early-afternoon thunderstorm.

Senior Weatherzone meteorologist Jacobus Cronje said high pressure systems over Australia's interior had blocked many moisture-laden cold fronts. 

"Up until the middle of the month, we are going to see the odd shower, nothing significant," Mr Cronje said.

But NSW in October is set to receive average or slightly above average rainfall, meaning a wet 10 to 15 day period in the second half of the month.