A SWARM of insects almost triggered a storm warning for southeast Queensland after it was spotted hovering across the Bureau of Meteorology's radar screens.

The Courier Mail reports forecaster Bruce Gunn said the swarm of what they believed to be locusts were spotted in the Warrego area, heading towards Charleville in southwest Queensland, on Saturday evening.

"The radars at the Bureau are very sensitive and will detect anything like smoke or insects, or bats, if there's enough of them.

"We did notice on a few of the radars towards sunset on Saturday there was a low level noise across three or four of the screens simultaneously," Mr Gunn said.

"The only thing we could think of was insects."

He said occasionally the insect swarms were visible on the website radar as "splashes of white".

"The display systems at the bureau are more sensitive and show up more colours," Mr Gunn said.

Meanwhile, the Bureau of Meteorology recorded temperatures well-below average across southeast Queensland yesterday morning thanks to a cool dry air mass.

Forecaster Vikash Prasad said in Brisbane the mercury fell to 13.8C in the CBD and 12.8C at Brisbane Airport, up to five degrees below the November average.

"The temperatures were not a record with a low of 8.3C recorded at the airport in November 2006," Mr Prasad said.