This spring has been cool and wet, defying dire drought predictions for the region in terms of snowpack.
Snow levels in the West Kootenay region are increasing, according to June 1 data. Snowfall survey and water supply report — 79% of normal in May, up from 66%.
A preliminary report produced by the BC River Forecast Centre stated that snowpack remaining in the basin remains stable and relatively dry across the province (averaging 57 per cent).
In the West Kootenays, snowpack has risen to the third highest basin percentage in the province, behind only the South Thompson (87 per cent) area and Stikine (160 per cent).
As of June 15, snowpack in British Columbia is extremely light, averaging 57 percent of normal, compared with last year’s provincial average of 91 percent.
“So far this year, 31 percent of the peak snowpack has melted, due to melting in low-lying areas in April and a heat wave from May 9 to 12,” the report said. “Last year, temperatures were much warmer and 43 percent of the snowpack had melted by this time.”
On average, 17 percent of the seasonal snowpack melts by May 15. Last year, snow melted so quickly during May that the state average on June 1 was 29 percent of normal.
Most regions began the snowmelt season with less snow than in 2023. However, this year’s lower snowmelt rates at higher elevations led to higher Snow Cover Index (SBI) values on June 1 for most regions.
Still, lower than normal spring flood risk is expected to continue this season for most of the West Kootenay and Boundary regions due to low snowpack, but localized flooding from extreme rainfall over the next six weeks remains possible.
“Low snowpack, forecast seasonal runoff and warm weather forecasts, combined with the lingering effects of the ongoing drought, have significantly increased the risk of drought this spring and summer,” the report explained.
Rain and Snow
In general, precipitation in May was below average across the Kootenay region as well as much of the province.
The start of the snow melt season has been uneven across the province, with shallow snowpack melting early, particularly in low to mid-elevation areas of BC’s Interior Plateau, and many of these areas currently snow-free.
“Due to cooler temperatures in late April, snowpack in higher mountain areas has been slow to melt, and some areas have experienced additional late season snow accumulation during the recent period of unsettled weather,” the report explained.
Weather Possibility
An El Niño watch remains in effect, according to the National Weather Service’s Climate Prediction Center.
El Niño is a warm phase of the El Niño Southern Oscillation (ENSO), which means warmer winters across British Columbia tend to result in lower than average snowpack and earlier melt.
The CPC predicts that a transition to ENSO neutral conditions is imminent.
“A La Niña watch remains in effect from the CPC, indicating an increased chance (49 per cent chance) of a La Niña event developing in June through August, possibly continuing into the fall/winter of 2024-25 (next year) and impacting British Columbia,” the report noted. “La Niña winters are relatively cool and wet, so persistently cool temperatures could delay snowmelt.”
Environment and Climate Change Canada’s (ECCC) seasonal weather forecast continues to indicate a moderate chance (40 to 95 per cent chance) of above-normal temperatures across British Columbia through June and July.
The current forecast for May through July is calling for above-normal precipitation across parts of the Southern Interior and Kootenays.
Spring is coming
The International Kootenay Lake Management Committee (IKLBC) declared “spring runoff” on Kootenay Lake on April 16, the earliest in the last seven years and two weeks earlier than 2023. As a result, spring runoff has begun.
Despite low snowpack on West Kootenay Lake, currently at 79 per cent of normal for the first few months of 2024, Fortis BC is “in compliance with the IJC approved orders for Kootenay Lake and is preparing for the onset of the spring snowmelt,” said Martin Suchie, Canadian executive director of the International Kootenay Lake Stewardship Council (IKLBC).
He said hydrological conditions in the Kootenay Lake basin this late winter and early spring have been showing to be worse than normal.
Sackey said the U.S. Department of Agriculture’s Natural Resources Conservation Service (NRCS) is reporting similar rates across the region, with the Kootenai Basin reaching 82 percent of its 30-year record normal.
tape measure
At the time of the declaration, the water level of Kootenay Lake in Queens Bay was 1,739.29 feet (530.14 metres), according to figures released by the board.
“Inflow into Kootenay Lake is at 22,800 cubic feet per second and is forecast to continue to increase over the next month,” the IKLBC release noted.
Kootenay Lake at Queens Bay reached its annual lowest daily mean elevation of 1,739.22 feet (530.11 meters) on April 13-14, 2024.
