Hot in Canberra city: scientists - The Canberra Times

Canberra High year 10 students Jeremy Bradbury and Triska Hoelzl escape the heat at the Big Splash water park with water filled balloons. Photo: Jay Cronan

The capital recorded its hottest day since February on Thursday but a cold change means our jump-start on summer won't last.

Thursday's high of 33 degrees was perfect swimming weather for the year 10 outdoor education class from Canberra High at Big Splash Waterpark.

''Our kids love coming down to the pool, but it was lucky it was such an especially hot day. It was a beautiful,'' PE teacher Jessica Nelson said.

The night stayed warm as well; temperatures were expected to stay on 11 or 12 degrees, the hottest they've been since last summer.

But temperatures will be erratic for a while, dropping on Friday before heating up next week. Weatherzone meteorologist Ben Burney said a cold change was coming. ''There's going to be a cooling trend from tomorrow and that will turn to showers, so we could see a bit of rain across the region,'' he said.

From Friday, temperatures will drop to about 22 with the possibility of 5-10 millimetres of rain.

The change will continue over the weekend, with cool but pleasant days and clear skies.

''It's going to be sunny skies over the weekend, pretty pleasant. It's going to be a great weekend really to get outside,'' Mr Burney said.

For warm weather lovers, he said the heat would be back from next week, and Tuesday was expected to top Thursday's temperature.

''It will be a much longer warm spell than this one, from Monday through to Wednesday. Tuesday is expected to be 34 degrees, so even hotter than today,'' he said.

But as summer officially begins on Sunday we may soon find ourselves looking longingly to the heavens; the latest Bureau of Meteorology modelling suggests a drier-than-average summer for most of the eastern states.

The bureau's three-month outlooks released this week also show the eastern half of the state has a 60 to 65 per cent chance of a warmer summer than usual.

And the CSIRO says extreme weather events - especially droughts and elevated bushfire conditions - are also becoming more likely across south-eastern Australia because of climate change.

In a peer-reviewed paper published on Thursday by Nature Geoscience, CSIRO research scientist Wenju Cai says warming along the tropics is already creating changes to dominant climate systems, influencing rainfall patterns.