The May 1 Yukon snow survey bulletin and water forecast has been released by the Yukon government’s water resources branch.
The bulletin provides long-term snowpack averages, monthly data and current snow depth and snow water equivalent observations for 52 locations in the Yukon and five locations in the neighbouring areas of British Columbia and Alaska.
The snow survey found that most of the territory was slightly above to well above average for this time of year, according to a statement by Jake Wilson, a communications analyst for the territory’s department of Environment.
“The snowpack has increased in all basins owing to a much wetter than normal April, with most stations recording well above average precipitation that fell as snow,” the statement read. “Average monthly temperatures for April varied around normal, however the north and west parts of the territory were notably colder than average. Colder temperatures and cloudier than normal conditions slowed snowmelt, particularly at higher elevation.”
Every March, April and May, the territorial government conducts Yukon-wide snow surveys to help forecast water levels and flow conditions across the territory. The May 1 snow survey is the last snowpack survey for the season.
The snow survey and water forecast provide a summary of winter meteorological and hydrological conditions for major Yukon watersheds.
The survey report shows that additional snowpack accumulations and delayed snowmelt, will increase the likelihood of a shorter freshet period.
The result of this is an elevated flood risk, according to the survey, noting that the risk is mostly in small to medium sized rivers with lower risk on larger rivers including the Yukon River.
“While water levels are expected to be above average, peak freshet flood risk to Yukon communities on large lakes and rivers remains low,” it reads. “The current snowpack compared to the historical peak snowpack is more informative of flood risk and more closely matches the April 1 snow survey.”
The survey shows that “high snowpack is one of several risk factors which influence flood potential during the spring breakup and snowmelt period.”
Spring weather, in addition to the “timing and progression of snowmelt, as well as spring precipitation events,” according to the survey, “are also important drivers of flooding regardless of snowpack levels.”
The survey adds that while many parts of the territory are showing well above average snowpack for this time of year, the April snowpack is much more indicative of flood risk. However, flood risk is elevated relative to the April assessment as a result of the late onset of snowmelt and additional snowfall.
Contact Patrick Egwu at patrick.egwu@yukon-news.com