B.C. is in the midst of a potent Pacific low, feeling the effects along the coast — from heavy mountain snow to copious rainfall and blustery wind gusts. While those impacts won’t be a welcome to residents, the warmer temperatures certainly is after last week’s prolonged cold snap. Rainfall amounts along western Vancouver Island could top 100 mm, while some mountain passes may see locally 50+ cm of snow. Winter storm, wind and snowfall warnings are in effect. More on what to expect Sunday and beyond, below.
SUNDAY AND BEYOND: STORMY AND WINDY, BUT MILDER
A Pacific low sliding south along the B.C. coast continue to bring a bout of heavy snow, rain and strong winds as the weekend draws to a close, contuining into early this week.
As warm air advances from the Pacific, the snow will change to rain for lower elevations of Metro Vancouver Sunday morning as temperatures rise. However, the change from snow to rain over areas of higher terrain will be delayed. Periods of heavy precipitation can produce snow as some cold air lingers.
Snowfall accumulations of 5-15 cm are expected over higher terrain of the Lower Mainland by Sunday afternoon.
The system is spreading mixed snow and rain over inland Vancouver Island. Additional snowfall accumulations up to 10 cm can be expected over lower terrain before precipitation transitions to periods of rain Sunday afternoon. There is also a risk of localized freezing rain in the morning as warm air advances over the region.
Southwestern Vancouver Island will be the target of the heaviest rains, with 100+ mm expected. Metro Vancouver, meanwhile, could see 30-50 mm of rainfall, with 20-30 mm for the rest of the Lower Mainland.
Significant mountain pass snow is forecast through Monday. with 50+ cm of snow forecast for the Sea to Sky, 15-30 cm forecast for the Coquihalla from Hope to Merritt, and Allison Pass from Hope to Princeton. Winter storm and snowfall warnings in effect.
In addition to the rain and snow, winds will be quite intense for the B.C. coast. Southeast winds through the Strait of Georgia will bring wind gusts of 70-90 km/h through pre-dawn hours Monday. There will be the risk of power outages.
Avalanche terrain should be avoided as the avalanche danger rating will be high through Monday for the South Coast, Vancouver Island and Sea to Sky — from the alpine to below treeline.
Freezing levels will climb to 700 metres on Sunday, creating a flood risk as rain moves into the mountain passes, but dropping once more to 300 metres Monday. This will bring the chance for more low-elevation snow to the South Coast.
Temperatures will rise above the freezing mark Sunday for western coastal sections, with milder Pacific air expected to spread east into the Interior by Monday, featuring daytime highs hovering around 0°C.
Beyond, an active pattern is expected for most of this week, with the potential for Arctic air to briefly return during the middle of next week. With it, there will be some potential for snow levels to drop back down to near sea level.
Thumbnail courtesy of Bam Dixon, taken in Burnaby, B.C.
Check back for updates as we continue to monitor this system.