Westerly winds on the Southern Downs give rise to unique 'mountain wave' cloud formation
The strange shapes were spotted from the Southern Downs all the way to the Gold Coast during Monday morning and afternoon.
The weather bureau said the clouds formed as westerly winds passed over the Main Range.
Senior meteorologist Peter Stapleton said "mountain waves" are commonly caused as air travels over terrain, but certain conditions must be met for the streaks to become visible.
"You have to have enough moisture to actually form the cloud and then the atmospheric layer that it's in has to be stable enough to trap that wave," he said.
"There might have been waves in other layers of the atmosphere, but because the moisture wasn't there, the cloud didn't form.
Mr Stapleton said these types of cloud are often more recognisable when they form at the tops of mountains, as 'UFO-like' shapes.
"I think they do have the formal name of lenticular cloud, but I think they're more colloquially known as a wave cloud or cloud streaks," he said.
"These have formed because of flow over a mountain but instead of forming the cloud on the mountain peak, it's actually formed in the wave that comes off the mountain and travels."
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