Environment Canada issued a winter storm warning Tuesday morning with the first major snow storm of the season expected to hit the GTA.

A blast of snow is expected for the GTA that could dump up to 30 cm of snow on the region by Wednesday afternoon.

Environment Canada says periods of light snow could begin to fall over the area starting late Tuesday .

A band of lake effect snow might add to the accumulation in areas near the west end of Lake Ontario Tuesday morning.

The snowfall is expected to pick up overnight and then taper off Wednesday afternoon with accumulation between 20 and 30 cm.

Stay off the roads

Police are urging motorists to avoid non-essential travel when the storm strikes.

Sgt. Tim Burrows suggests commuters work from home or take public transit and leave extra time.

"If you don't have to drive, don't," Burrows says.

"The less cars we have on the roads tomorrow, the more efficient snow removal will be. And realistically, the safer the roads will be."

Burrows also advises those that do hit the road to drive according to not only weather conditions, but the condition of the vehicle and its driver.

Drivers behind the wheel of a 4x4 or SUV are also reminded that their vehicles may be better to get out of heavy snow, but they don't stop or slow down any better than a regular car.

City ready to clear the mess

Crews from the City of Toronto are ready to tackle the snowfall beginning Tuesday afternoon, when salting is expected to begin as soon as the snow starts to fall.

"The salters will be getting out there right away," says Transportation Services Director Myles Currie.

As accumulation builds, Currie says major routes are likely to be plowed a several times. It won't be until 18 hours after the storm that smaller side streets will be cleared of snow.

Currie asks people not to park along streetcar routes so that plows can clear the snow.

Snow to snarl travel

The national weather agency says people should change their plans to avoid "unnecessary travel" during the storm since driving conditions will be dangerous.

Already, dozens of flights from Pearson International Airport were cancelled or delayed due to snow in areas like New York, Chicago and Detroit.

Air Canada has issued a travel warning for several cities - including Toronto - due to weather.

At Billy Bishop Island Airport, Porter Airlines is warning passengers to check their flight status before arriving at the airport. The airline says delays and cancellations "may occur."

While the snow may be grounding air travel, rail travel is expected to pick up the slack. VIA Rail says it is ready to handle an increase in demand by adding extra cars to its trains between Ontario and Quebec. 

For indepth coverage of the snow storm and to find out about closures and cancellations, click here.