If you thought it was a bit warm on Saturday, Sunday is set to be even hotter.
Saturday's temperature peaked at 36.9 degrees, pretty much right on the forecasted top of 37, about 4pm. Sunday is forecast to hit 39 degrees. That puts it on track to be the hottest day this summer so far.
It was also a hot night. The temperature didn't drop below 20 degrees until after midnight, and only dropped to 16.5 degrees about 6am. Then it started heating up again. It passed 30 degrees shortly after 9am.
There is, though, a slight (30 per cent) chance of a shower or thunderstorm Sunday afternoon or evening. But if the rain does come, it's unlikely to be much - just 0.4mm is forecast in the event of a downpour.
There's a very high fire danger, and the UV index is predicted to reach extreme (level 15).
Thankfully, there's a bit of a reprieve forecast for Monday, when the temperature is expected to drop to a comparatively cool 30 degrees. There's also a medium (40 per cent) chance of showers, most likely in the morning and afternoon. There's also the chance of a thunderstorm in the afternoon and evening.
The rest of the week is forecast to be similar, with temperatures topping out in the high 20s and low 30s.
Bureau of Meteorology duty forecaster Andrew Haigh said this was a typical pattern of weather for a Canberra summer.
With light winds currently over central Australia, a lot of heat was able to build up, Mr Haigh said.
A front approaching the capital from the south-west meant north-westerly winds were bringing the extreme heat to the region.
Mr Haigh said Canberra could expect a few more similar periods during the summer.
ACT Health recommends people remain hydrated during the extreme heat. They urge people to avoid alcohol or caffeine, particularly if dehydration is suspected, stay out of direct sunlight and avoid strenuous activity in the heat of the day.
Infants and children, pregnant women, the elderly and people with pre-existing medical conditions are at greater risk of heat related illness.