Spectra, which has been illuminating Aberdeen buildings and landmarks with some world-class light and sound installations, will not go ahead tonight.
The event has been running over the weekend but heavy rain and wind speeds of 50mph have forced organisers to bring the festival to an early close.
A statement from Spectra said: "We have worked very hard to try and keep Spectra up and running despite Storm Dennis’s efforts, however the safety and enjoyment of our visitors is paramount and unfortunately, due to extreme and changeable weather conditions, we are disappointed to have to cancel this evening’s event.
"We’d like to say a huge thank you to those who came and shared the return of Spectra with us this year."
Spectra has been a feature of Aberdeen's festival calendar for a number of years and returned in 2020 after a break last winter.