That's as winter storm warnings continue for all of the north country except northern parts of St. Lawrence County.
The new snowfall forecast is in addition to the approximately 6 to 10 inches of snow that was expected to fall in the three counties through Wednesday night.
With a snow-laden winter storm forming over central Alberta, Environment Canada issued winter storm warnings late Wednesday morning for Calgary, Airdrie and much of southern Alberta.
Winter storm and snow fall warning issued
The snow won't be as heavy in northern St. Lawrence County, where there's a winter weather advisory until 11 p.m. Wednesday.
"Really from Watertown south, you'll see at least some form of a decent amount of snow", said Steve Welch, meteorologist for the service's Buffalo office. "The snow is expected to end Friday".
As of Tuesday afternoon, Environment Canada was forecasting the heaviest amounts of snow will begin overnight Wednesday into Thursday, but "there is still uncertainty where the heaviest amounts will fall". Although winds combined with a surface warm front will increase temperatures, there is also concern for gusty winds blowing fresh snow and reducing visibilities at times in certain areas. Snowfall accumulations up to 25 cm are expected before conditions improve Thursday evening as the system moves out of the region and weakens.More news: Saudi Arabia denies granting airspace for flights between India and Israel
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