B.C.’s River Forecast Centre has issued the first of their Snow Survey and Water Supply Bulletins, which give a snapshot of snow conditions across the province.
At the time of the survey (January 1, 2020) the East Kootenay snow pack was at 97 per cent of normal, keeping in mind that a lot more snow has fallen since that date of the survey.
Fall and early winter weather had been variable across the province, the report says. October featured persistent cold weather, with temperatures -0.5 to -3.5˚C below normal across most of the province. Eastern British Columbia in particular was far below normal. With the dominance of arctic air masses over the province, precipitation was also generally below normal. In November, temperature patterns switched, bringing an extended period of warmer than normal conditions across most of the western portion of the province and the north-east (+0.5 to +4˚C above normal), and closer to normal temperatures towards the south-east. Precipitation was well below normal in south-west BC (typically 30-70% of normal), above normal in the north and north-east, and slightly below normal for other areas of the province. Through December, minimum daily temperatures were well-above normal through southcentral, south-east, north-west, and north-east BC, and slightly above normal in other areas. Precipitation was above normal through east-central BC and areas of the Interior Plateau, and below normal through areas of south-west BC. Since mid-December, BC has transitioned to a more persistent storm period, with several frontal and atmospheric river systems impacting the province and bringing heavy precipitation to most areas of the province. Temperatures have been varied during these storm events, which have generally brought increased snow accumulation at mid and high elevations, and heavy rain to lower elevations. These patterns have persisted into early January. With a manual snow survey window for data collection of 7 days before or after January 1st, surveys conducted at the early period of the window may not have fully captured the rapidly changing snowpack conditions over the past couple of weeks; overall snowpack values across the province have been trending upward since January 1st.
As for the outlook for the next few months, the bad news is the trend of cooler temperatures is likely to continued.
“Seasonal weather forecasts from late December from Environment and Climate Change Canada are indicating an increased likelihood of cooler than normal temperatures for January through March for southern BC,” the report says.
By early January, nearly half of the annual BC snowpack has typically accumulated. At this early stage in the season snow accumulation is extremely variable across the province. High snowpacks in the eastern mountains of the province are being offset by low snowpack in the Coast Mountains and Vancouver Island, such that the overall snowpack across the province is considered below normal. However, with three or more months left for snow accumulation, seasonal snowpacks can still change significantly. However, trends that are currently present would be expected to persist if weather patterns are seasonal over the remainder of the winter and early spring.