Queensland frost alert: Sub-zero cold snap predicted

An extreme Antarctic weather system is set to impact Queensland with a significant influencer of climate just recording one of its strongest levels on record.

Widespread frosts and subzero temperatures are forecast for Queensland over coming days ahead of what is shaping as a brutally cold winter.

The Southern Annular Modular (SAM), a significant influencer of climate in Australia, has just recorded one of its strongest levels on record.

The “exceptionally high” value of +4.2 was recorded by meteorologists on May 13 and is among the top nine highest values reported in over 50 years.

A climate driver is indicating more snowy, rainy weather this winter. Picture: WeatherZone

The figure reaffirms Australia will be impacted by a positive phase of the SAM this winter.

“A positive phase of the SAM during winter moves the rain and snow-bearing cold fronts further south and causes easterly winds to increase over eastern Australia,” WeatherZone meteorologist Ben Domensino said.

“This typically reduces rainfall and snowfall over parts of southern Australia and allows more rain to fall in parts of Queensland and NSW.”

Queensland will get another taste of an early winter this weekend with widespread frost and freezing temperatures forecast.

This graph shows fluctuations between negative and positive SAM periods between January 2021 and April 2023. Picture: WeatherZone

Senior meteorologist Harry Clark said Brisbane could expect the mercury to hover around 9C in the mornings, with Ipswich dipping to 3-4C.

It could drop to as low as 0C across the Darling Downs, particularly in Oakey, Warwick and Stanthorpe.

“Certainly quite cool mornings coming up, and I guess once you get down to sort of as close to 0C temperature as we can start getting frost,” Mr Clark said.

Even the maximum temperatures are giving Queenslanders a reason to keep their winter woollies handy.

“Maximums are on the cool side of things as well, generally low 20s for Southern

Widespread frosts are predicted for southern Queensland this weekend.

Queensland, 20s through Central Queensland and high 20s for Northern Queensland, generally a couple of degrees below average,” Mr Clark said.

Southern Downs Region set the stage for the state’s coldest temperatures on Friday morning, with Applethorpe registering a chilly -0.6C, closely followed by Charleville at 0.3Cs, and Wellcamp airport at 0.6C.

What is the SAM?

The SAM refers to the displacement of the powerful westerly wind belt which flows around Antarctica all year.

These winds carry cold fronts and low pressure systems which are responsible for seasonal rain, snow and wind in southern Australia.

It can have a recognisable influence on weather in different parts of Australia, though the influence is usually at its strongest during winter and summer.

Phases typically last for around one to two weeks and the fluctuation between positive and negative can be random and difficult to predict.

The SAM index has come close to reaching its current height twice in the last two years – in January 2022 and January 2021, according to US Climate Prediction Centre data.

Originally published as Queensland frost alert: Sub-zero cold snap predicted