Rainfall Warning - High streamflows and rain on snow forecast for Sea to Sky Corridor

Nov 21, 2017
Affected Communities: 
District of Squamish, Electoral Area C, Electoral Area D, Resort Municipality of Whistler, Village of Pemberton

UPDATE: November 27, 2017 (11:00 a.m.) - The High Streamflow Advisory has ended. 

UPDATE: November 23, 2017 (9:30 a.m.) - The Rainfall warning for Howe Sound has ended. The High Streamflow Advisory is still in effect. Several impacts were experienced overnight throughout the SLRD as a result of the heavy rain / rain on snow event - read the summary here.  

Note from the SLRD (10:30 a.m., Tuesday, November 21, 2017):

The SLRD Emergency Program has been advised by Environment Canada and the BC River Forecast Centre that an extreme weather event (heavy rain, rain-on-snow) is expected over the next 48 hours. 

The Rainfall Warning below impacts SLRD Areas C and D, the District of Squamish, Resort Municipality of Whistler and Village of Pemberton. A High Streamflow Advisory is also in effect for Howe Sound and Sea to Sky - see related notice for details. 

However, please note that weather throughout the SLRD is expected to be very poor over the next two days, and conditions will make highway travel treacherous. Please see the related travel advisory, in effect for the entire SLRD, as well as the notice from Drive BC advising that the Duffey Lake Road portion of Highway 99 is subject to closure due to high avalanche hazard. Non-essential travel over the next 48 hours is not recommended.

The SLRD Emergency Program is working with its member municipality and First Nations partners to monitor for impacts, and may activate an Emergency Operations Centre if required. Updates to this notice will be provided as required.  


An atmospheric river, (Pineapple Express) is forecast for the Sea to Sky area over the next 48 hours. Environment Canada and The BC River Forecast Centre have advised that up to 150mm of rain is possible by Thursday for Howe Sound, up to 100mm for Whistler and up to 80mm for Pemberton.

With the forecast also predicting a sharp rise in freezing levels to approximately 3000m, rain on snow is also predicted which will add to volumes in rivers and tributaries. High streamflows are expected on the Lillooet River with rising levels also expected on the Squamish and Stawamus Rivers.

Overland flooding is possible in low lying areas and extra caution should be taken when travelling due to heavy downpours and water pooling on roads. Delay travel where possible, remember to check Drive BC before departing and leave plenty of extra travel time to allow for conditions. Exercise high caution near riverbanks and streams and avoid these areas where possible as water levels and bank stability can change suddenly. 

SLRD residents experiencing flooding are asked to contact SLRD Emergency Program Manager, Ryan Wainwright:

 

 

Applicable Service: 
Inside the SLRD > Notices > Emergency Notice Travelroad Notices Weather Noticess > Rainfall Warning - High streamflows and rain on snow forecast for Sea to Sky Corridor