A spring storm is likely to drop 10 to 20 centimetres of heavy snow on southeastern Saskatchewan this week.

Environment and Climate Change Canada issued a special weather statement, saying "A significant spring storm is set to bring a mix of rain and heavy snow to portions of southern Saskatchewan and southwestern Manitoba on Tuesday night into Thursday."

The agency said forecasting this system - as is often the case with late-season storms - has been "quite a challenge."

"There remain to be uncertainties with the evolution of this system, ranging from timing the onset of rain turning to snow, snowfall totals, and the corridor of heaviest snowfall. In general, various model guidance remains muddled, with little in the way of a consensus of areas affected and total precipitation amounts."

You can expect the heaviest snowfall on Wednesday morning. If you plan on travelling, you can check on highway conditions here.

"Total accumulations of all types of precipitation may exceed 20 mm for some areas, greatly exacerbating the flood situation for some regions," said the statement.

Indications are that eastern Saskatchewan and western Manitoba will get hit the hardest.

"The highest confidence for the heaviest precipitation lies over eastern Saskatchewan and western Manitoba, roughly from Regina to the Manitoba Parklands. The greatest uncertainty lies over western Saskatchewan, west of Regina, and the eastern Red River Valley. Gusty winds will also be a concern, in addition to the snow, with moderate to strong easterly winds leading to poor travel conditions, particularly on Wednesday."

You can find more information here on the looming system.