A band of multiple snow squalls is continuing its trek across the region south and east of Lake Huron and Georgian Bay today.

Environment Canada says the main storm off Georgian Bay currently extends inland from about Thornbury southeast to near Angus. The weather agency says up to 30 centimetres of snow may have fallen already, and another 10 centimetres are possible this afternoon.

The storm is then expected to move east and weaken by tonight.

A snow-squall warning is in effect for Owen Sound, Blue Mountains, Northern Grey County, Innisfil, New Tecumseth, Angus, Barrie, and Collingwood.

Skies are clear in Barrie this afternoon, but snow is falling heavily in Collingwood.

Meanwhile, London received about 30 centimeters of snow overnight from the squalls coming off Lake Huron. In some places near London, however, that amount was closer to 50 centimetres. Environment Canada is predicting another 15 centimetres could fall there today.

On Nov. 24 last year, Environment Canada reported eight centimetres of snow on the ground in Barrie, and that increased to 21 centimetres by Nov. 26, 2012. The snow base went away on Dec. 3 and returned for the season on Dec. 22, 2012. In 2011, the weather agency reported no snow on the ground until Dec. 9 but accumulation was sporadic until Dec. 28, 2011.

Winter officially starts Dec. 21.