Where's winter? Sydney's unseasonably warm May weather is set to continue through this week, the Bureau of Meteorology said.

The temperature is expected to hit 22 on Monday and Tuesday, climbing to 24 on Wednesday before cooling off slightly later in the week.

Early morning sunrise at Balmain: The mercury has peaked above 20 degrees every day since Monday. Credit:Peter Rae

The city is currently experiencing a warmer than usual May with the temperature for the month so far sitting nearly one degree Celcius above the May average.

"We've been travelling a bit above the average for May," said Steph Spackman, a duty forecaster at the Bureau of Meteorology. "We've only had three days below 20 degrees."