Many parts of B.C. are heading into uncharted drought territory this summer after a record-breaking snowmelt this spring.
New data released this week by the BC River Forecast Centre shows many alpine snowpacks have completely melted well ahead of usual.
Across B.C., snow depths are just 29% of normal for this time of year.
“The hottest May on record for B.C. generated extremely rapid melt of the provincial snow pack. Many mid and high-elevation automated snow weather stations measured record low snow for June 1st or recorded the earliest snow-free date of the season,” said the forecast centre.
The North and South Thompson, Similkameen, Kootenays, Upper Fraser and Cariboo all have weather stations that either went snow-free at their earliest date ever, or measured record-low snow for June 1.
The Okanagan and Similkameen basins are now statistically snow-free while the Boundary is at just 4% of normal. The North Thompson (16%), South Thompson (33%) and Fraser River (24%) are also all well below normal.
The BC River Forecast Centre says this year is such an outlier when compared to historical data, “predicting possible scenarios and impacts is particularly challenging because no strong analogues for 2023 exist on record in B.C.”
The BC Wildfire Service is bracing for what could be the worst fire season on record.
It is possible, however, that should rainfall arrive later in June that would make the wildfire situation less volatile. In 2019, snowpacks were extremely low on June 1, but a cooler and wetter first part of the summer led to a quiet fire season and less severe drought conditions.
“Long-range precipitation is difficult to forecast accurately over long lead times, therefore creating uncertainty over how the 2023 summer season will play out,” said the river forecast centre this week.
“While continued dry weather would drive extremely low flows this season, there is a chance that wet weather could dominate the summer season (e.g. 2019) and at least partially ease the risk of low flows.”
The Similkameen, Coldwater and Salmon rivers are already in a stage three drought on a one-to-five scale of severity. All other rivers in the Thompson-Okanagan and Kootenays are at drought level two.