Weather
February was dominated by persistent high pressure over British Columbia and offshore which generally brought stable, dry, cold weather conditions across the province. This pattern of stable weather was interrupted at times with periods of instability which brought light to moderate precipitation, including snowfall at low elevations. A strong atmospheric river event in the middle of February brought heavy rain and seasonally warm temperatures to south-west BC, leading to the melt of low elevation snow.

For the month of February, temperatures were 1 to 4˚C below-normal through most of BC, except in the north, where temperatures were slightly above-normal. Overall precipitation patterns for February were mixed across the province, with drier conditions in the north coast and west-central areas of BC, wetter conditions in the South Coast, South Interior and Kootenay, and near normal precipitation elsewhere in the province.

Weather across the entire winter period (December, January and February) tells a similar story, with persistent colder than normal temperatures (1-3˚C) over the southern half of BC, and warmer than normal temperatures over the north. Dry conditions have been prevalent over most of the province this winter.

Snowpack
Weather patterns through February led to modest shifts in snow pack conditions across the province. In the South Interior and south-east BC, snow basin indices saw increases in values from February 1st. Declining snow basin indices occurred in coastal and northern BC, while indices in central locations were generally stable from February 1st values. The provincial average for all March 1st snow measurements is 85% of normal, which is an increase from the average of 79% in February.

Snow basin indices for March 1st 2017 range from a low of 45% of normal in the Liard to a high of 99% in the East Kootenay (Table 1 and Figure 1). Below normal snowpack (65-80%) is present in the Upper Fraser, Vancouver Island, Skeena-Nass and Northwest, and well below normal (<65%) in the Boundary, Stikine, Liard and Peace. Near-normal snowpack (80-100%) are present throughout the rest of the province. The March basin index for the entire Fraser River basin is at 83%, which is approximately a 1-in-15 year low snowpack or the 10th lowest March index in the past 65 years.

With cooler than normal temperatures through this winter, low elevation areas have been cold enough that they have experienced a greater proportion of precipitation as snow than normal. For example, most Environment and Climate Change Canada weather stations that record snow observed 2 to 8 times the normal snowfall amounts in February. This season’s snowpack can be considered “upside-down”, with higher than normal snowfall occurring at low elevations, but below-normal snow at high elevations. This is a result of colder than normal temperatures which have resulted in several low elevation precipitation events occurring as snow rather than rain. However, seasonally dry conditions have resulted in lower than normal snowpack at high elevations despite the colder conditions. Increased snow at low elevations plays a limited role in seasonal flood risk or water supply into the spring and summer.

Percentage of normal snow pack Boundary 58, Okanagan 86 and Similkameen 83  – Provincial average 85