Ministry of FLNRO

Snow Survey and Water Supply Bulletin - June 15th, 2016

The June 15th snow survey is now complete. Data from 5 snow courses and 62 automated snow weather stations around the province, collected by the Ministry of Environment Snow Survey Program and partners, and climate data from Environment Canada have been used to form the basis of the following report.

Click here for the Snow Survey and Water Supply Bulletin as a PDF file.
Click here for the complete June 15, 2016 Snow Survey Data.

Weather through the first half of June has generally been seasonable, with periods of unsettled weather and showers across the province. A high pressure system in early-June brought hot temperatures through southern BC. Since early-June a number of cold low systems have swept across the province, bringing cooler temperatures and wetter weather. Precipitation through the first part of June has been variable across the province, with below normal rainfall in western and southwestern BC, and above normal precipitation in central BC and the north-east.  

Snow packs are generally depleted at snow monitoring locations across the province as of June 15th, with only 12 of the 62 automated snow weather stations recording more than 50 mm of snow water equivalent. Where snow packs were sufficient to support melt, observed melt over the June 1st to June 15th period was typically in the 200 to 400 mm range. 

Snow basin indices are extremely low for the June 15th period. Since very few manual snow surveys are collected on June 15th (historically and for the 2016 survey period), snow conditions are largely interpreted from automated snow weather station data. As a result, many basins have limited data to assess snow basin index values.

Table 1: BC Snow Basin Indices – June 15, 2016


% of Normal


% of Normal

Upper Fraser West




Upper Fraser East






South Coast


Middle Fraser


Vancouver Island


Lower Fraser


Central Coast


North Thompson




South Thompson




Upper Columbia




West Kootenay




East Kootenay








  1.  ‘No Data’ indicates that no basin index snow surveys were conducted within the basin during this survey period.

Low snow basin indices for June 15th reflect the early season melt that happened this spring. Based on historic automated snow weather station data, conditions this year on June 15th are more typical of early-July conditions, indicating that this season’s melt continues to be 3-4 weeks ahead of normal.

Freshet runoff echoes the pattern in snow melt, with many rivers experiencing flow conditions that are 3-4 weeks or more ahead of normal conditions. While April runoff was generally well above normal across the province, flows eased as rivers have transitioned to the declining limb of the snow melt runoff cycle. Rivers across the Interior of BC are generally at 25% to 75% of normal flow levels for this time of year. These represent flows generally in the 5th to 15th percentile range. The exception to this is in the central Interior and in north-east BC, where flows are closer to normal, or even above normal, as the result of wet weather over the past few weeks. On Vancouver Island and smaller, non-glaciated drainage basins in south-west BC, river levels are extremely low for this time of year as the result of drier weather and early snow melt, with current flows typically in the 1st to 5th percentile range.

The Climate Prediction Centre at the U.S. National Weather Service/NOAA has ended their El Niño Advisory as sea surface temperature anomalies in the equatorial Pacific Ocean have declined to neutral levels. A “La Niña Watch” has been issued as modelling is indicating that La Niña conditions are favoured to develop by the fall-winter of this year. Seasonal forecasts from Environment Canada indicate an increased likelihood of above-normal temperatures across British Columbia over the June to August period.

Most rivers have experienced their peak levels for the year, unless an extreme rainfall event occurs in late-June or early-July.

The advanced freshet is expected to put pressure on summer low flows in snow melt- dominated rivers across the province. Through most of the province, the transition to seasonally lower than normal flows occurred. The influence of the snow melt season occurring about a month early this year is expected to continue through the summer, with the largest departures from normal flows occurring in late-June and through July. By August and into September, rainfall is an important factor in determining streamflow as the influence from snow melt diminishes.  While the impact of this will vary from river to river across the province, the proportion of flows in June, July and August that are derived from snow melt will be greatly reduced. In the northeast and in lower elevation coastal watersheds, snow melt usually plays a minor role in summer flows, and rainfall is particularly important for determining the flows that are experienced through the summer.

This is the final Snow Survey and Water Supply Bulletin for the 2016 season. The River Forecast Centre will continue to monitor streamflow and weather across the province, and issue Water Supply and Streamflow Bulletins throughout the summer as conditions warrant. Seasonal information on drought and drought levels is available on the BC Drought Information Portal.

BC River Forecast Centre
June 23, 2016