A very high fire danger warning has been issued for the Illawarra with the mercury forecast to hit 33 degrees in some parts of the region.
The temperature in Wollongong is expected to get to 32 degrees on Thursday with Albion Park and Nowra forecast for 33 degrees.
It will be slightly cooler on Friday with a top of 29 degrees expected in Wollongong.
The Shoalhaven also falls under the fire danger warning with the Rural Fire Service urging residents not to undertake any pile burning on Thursday.
On Monday, the Illawarra set a new heat record for April, with the Albion Park weather station recording a maximum temperature of 34.5 degrees.
Half a degree above the previous record, set on April 3, 2005, Monday’s maximum was more than 12 degrees above Albion Park’s average daily high for the month.
Bellambi Point weather station also recorded unseasonably warm temperatures, with the mercury hitting 31 degrees at 10.53am.
This was 2.2 degrees below the record from 2005, but nine degrees above the average April daily maximum.