The regional snowpack is at zero with drought conditions beginning to loom large as the summer wears on in the Kootenay-Boundary region, according to the latest Snow Survey and Water Supply Bulletin from the province.

As of June 15, the regional snow pack was at zero — with no measurable snow remaining compared to normal conditions — in the West and East Kootenay, as well as the Boundary, and substantially below normal, while averaging four per cent across B.C. Two weeks ago the snowpack — was at 29 per cent.

Last year, the June 15 average of all snow stations in the region was 215 per cent of normal — with the progression of spring snowmelt as delayed — due to the inability of the mountain snowpack to melt and continued unsettled weather conditions. 

In 2022, cool and unsettled weather conditions presided over the province into late spring and substantially delayed snowmelt. Fast forward one year and flood risk from snowmelt is largely over for the season, as most rivers have experienced their peak flows and are now rapidly declining.

Several factors have generated high risk of region-wide drought this year, including “lingering effects of fall 2022 drought, unusually dry and warm conditions prevalent in winter 2022-23 and spring 2023, exceptionally rapid and early 2023 snowmelt, and high likelihood of above normal temperatures this summer,” the bulletin noted. 

Many rivers are already at or near the lowest flows on record for this time of year, the provincial data showed, with seasonal forecasts from Environment and Climate Change Canada indicating a very high likelihood of above normal temperatures this summer (June-August). 

Outlook 

The seasonal record-breaking heat across the province in May signified the end of the past three years of La Niña cycles, as an El Niño phase begins its effect on weather patterns. 

The Climate Prediction Center (CPC) issued an El Niño Advisory on June 8, with El Niño conditions now in place. El Niño is forecast to gradually strengthen into winter 2023-2024. 

El Niño is the warm phase of the El Niño/Southern Oscillation (ENSO). Global average temperature tends to be higher in El Niño years than in La Niña or ENSO-neutral years, and El Niño winters are generally warmer and drier than normal. 

Seasonal weather forecasts from late May by ECCC indicate a moderate to strong (up to 90 per cent) probability of above normal temperatures for almost all of B.C. from June through August. 

Source: Snow Survey and Water Supply Bulletin

Dry land training

Several converging factors have generated high risk of significant drought this summer: 

– Lingering effects of drought conditions in summer and fall 2022. 

Some parts of the region carried a severe precipitation deficit into winter, meaning that an above-average amount of spring rainfall and snowmelt runoff would be required to return to more ‘normal’ hydrological functionality. 

– Unusually dry and hot conditions through much of winter 2022-23 and spring 2023. 

Although snow pack was near normal at its peak in winter 2022-23, the region had a much lower than normal overall snow pack. Precipitation recharge to snow pack and streamflow over winter was minimal. 

Source: Snow Survey and Water Supply Bulletin

By Timothy Schafer, Local Journalism Initiative Reporter

Original Published on Jul 07, 2023 at 01:08

This item reprinted with permission from   The Nelson Daily   Nelson, British Columbia
Comments are Welcome - Leave a reply below - Posts are moderated

Comments are Welcome - Leave a reply below - Posts are moderated