LONDON, ONT. -- Meteorological winter arrives on Dec. 1 and Mother Nature will deliver a blast of the white stuff.

A heavy snowfall warning has been issued for London-Middlesex, as well as Lambton, western Elgin, Bruce and southern Grey counties.

Rain will change to snowfall Monday night, and five to 10 cm of snow is expected in the warned areas overnight.

Environment Canada issues a snowfall warning when 15 cm or more of snow falls within 12 hours or less.

This storm will have you reaching for your shovels and packing your patience for your Tuesday morning commute. Expect snow-covered roads and blowing snow.

The low-pressure system is a slow mover, and snow will continue Tuesday with another 5-10 cm of accumulating snow.

Total snowfall in London could top 20 cm over the multi-day snowfall.

Most of the heavy snowfall is expected through the day Tuesday but there will be lingering bands of lake-effect snow flurries Tuesday night into Wednesday.

The storm moves northeast on Wednesday, and sunshine returns Thursday.