BC's snowpack is at 66% of normal, hot weather expected to lead to rapid snowmelt

The May 1 snowpack levels are in and paint a worrisome picture for most of British Columbia,

According to the province, the provincial snowpack is “extremely” low, averaging about 66% of normal across BC.

Last year, the province averaged about 91%, however, that changed drastically due to an unseasonal heatwave in early May, which caused rapid snowmelt across the Interior.

“Low snowpack and seasonal runoff forecasts combined with warm seasonal weather forecasts and lingering impacts from on-going drought are creating significantly elevated drought hazards for this upcoming spring and summer,” the province said.

Typically, the province’s snow accumulation reaches max levels in mid-April and the May 1 snow survey is meant to provide insight into possible late season snow, the timing of snowmelt and whether the melt is early, late, or following seasonal patterns.

According to the province, a high-pressure ridge is settling across the province, which means the rest of the week is going to be hot across BC with temperatures reaching the high 20s in the Interior and low to mid 20s in the north.

This is expected to lead to the first episode of rapid snow melt at higher elevations this season.

As spring settles and summer approaches, the snowmelt season has already begun and has been mixed across the province, the Snow Survey and Water Supply Bulletin said.

“In low-to-mid elevations, particularly in plateau terrain in the BC Interior, early melt of a shallow snowpack has occurred and many of these areas are now snow-free,” according to the bulletin.

The Brenda Mine automated snow weather station in the Central Okanagan melted to snow-free conditions sooner than ever recorded in 28 years.

“Higher elevation mountain snowpack has experienced a delay in melt due to cooler temperatures in late April, and some areas experienced additional late-season snow accumulation during recent unsettled weather periods,” the bulletin said.

Snow basins measurements range from 0% of normal in the Upper Fraser West to 171% in the Liard region north of Fort Nelson. The northwest basin is at 125% of normal levels.

“Extremely” low snowpack (<60%) continues to be seen in the Upper Fraser East, Upper Fraser West, Lower Thompson, Quesnel, Nicola, Okanagan, Similkameen, Vancouver Island and Skagit.

Basins in the Thompson-Okanagan region range from 71% and 80% of normal in the North and South Thompson, respectively, to 60% of normal in the Okanagan and 54% in the Similkameen.

Vancouver Island is at 49% of normal levels.

Seasonal outlook shows a hot start to summer

According to the Climate Prediction Center (CPC) at the US National Weather Service, more neutral conditions of the ongoing El Niño weather pattern, which bring warmer temperatures to BC, are expected into June.

There is a 60% chance of that shifting to La Niña conditions in June to August and likely continuing and impacting BC into the fall winter of 2024-25, bringing “relatively cool and wet” conditions.

However, until then, Environment Canada forecasts continue to indicate a “moderate likelihood” of above normal temperatures over the May to July period.

That is expected to continue contributing to drought conditions but there is a hope there will be delays in the melt of snow at higher elevations, which could have a “prolonged” influence on streamflows.

“There are concerns for drought this season due to long-term precipitation deficits, low snowpack and seasonal weather forecast throughout the province. Spring weather will continue to play an important role in summer drought conditions,” the bulletin said.

The next snowpack bulletin will be released on May 23 with numbers from May 15 surveys.