The Four Flagged Communities
The March 1 Yukon Snow Survey Bulletin provides the data underpinning the advisory. Snowpack across the Teslin/Big Salmon, Central Yukon (Carmacks area), White River, Liard, and Lower Yukon (Dawson/Klondike) basins is classified as well above normal. The Upper Yukon basin, including the Southern Lakes and Whitehorse area, is above normal but with more conditional risk — flood potential there depends on the timing of snowmelt, summer precipitation, and glacial melt.
The Teslin/Big Salmon basin is the most concerning. The bulletin estimates basin-averaged snow water equivalent at 248 millimetres, or 153% of the long-term normal, with cumulative winter precipitation in Teslin running at 170% of normal. These are not marginal increases. They represent substantially more water stored in the snowpack than the territory typically manages through the spring freshet.
Marsh Lake is the exception. Average snowpack combined with below-average groundwater levels gives the lake ample capacity to absorb spring inflows, and flood risk there is considered low.
The Weather Trigger
Environment and Climate Change Canada expects April to be colder than average across the Yukon, followed by a shift to hot, dry conditions in May. That sequence — delayed melt followed by rapid sustained warmth — is precisely the pattern that produces the most dangerous snowmelt flooding. Snow accumulates longer, stores more water, and then releases it over a compressed period once temperatures rise. If rain coincides with the melt, the risk escalates further.
A Yukon government hydrologist told CBC North that officials are awaiting April 1 snow surveys and ice thickness measurements to better assess ice jam risk for the Klondike River — a variable that can cause sudden, localized flooding that is difficult to predict in advance.