Last month was the warmest May for night time temperatures in the ACT in 19 years, with the average minimum sitting at 5.9°.

There was only one sub-zero morning, compared to the long term average of eight.

Daytime maximums were also warm at 18.1°, compared to the recent average of 16.6°.

The official rainfall total of 62mm was the most for four years, and well above the long term average of 29mm.