The ridge of high pressure remains anchored on the B.C. coast giving dry, hot conditions to southern BC
(Avalanche Canada forecast) – In the absence of wildfire smoke, favoured areas for all-time temperature records for August are the Alberni Valley, Howe Sound-Whistler-Pemberton corridor, the Fraser Valley, Fraser Canyon and South Thompson valleys. Temperatures in these areas will soar into the mid to high 30s today through Friday. HOWEVER, the location and concentration of wildfire smoke has the potential to significantly inhibit the amount of solar radiation reaching the surface, lowering daytime maximum temperatures. This phenomenon has already been observed over the last two days where the number of communities setting records have been kept to a minimum.
Temperatures in the mid to high 30s will stretch across most of southern B.C., with daily temperature records possible in western parts of the Kootenays and Columbias. Further north, temperatures in Prince George, Bulkley Valley and the Chilcotin – Cariboo will remain steady near thirty under the presence of the ridge.
As the ridge strengthens over the province, light winds and stagnant conditions combined with forest fire smoke will lead to a deterioration of air quality. See the Special Weather Statements issued by Environment Canada for both the heat and air quality issues. The only good news for fire fighters this week is that wind speeds will be generally light and no thunderstorms are forecast.
The only active weather in the province today is associated with an upper trough moving through northeastern B.C. as shown in the 500mb animation above. Here, scattered showers and thunderstorms giving locally heavy downpours are expected through this evening for the northern Rockies, Fort Nelson and the Peace regions. Elsewhere, clear skies under the dominant ridge prevail through Friday.
On Saturday, the surface trough shifts inland allowing a surge of stratus to push up the U.S. coastline and onto the west coast of Vancouver Island. In addition to cloud cover and possible drizzle, temperatures will cool by a few degrees in many areas of the south coast. Very slight cooling is also expected throughout the interior as the upper ridge weakens. The models are continuing to hold off the thunderstorm risk for the interior until at least Sunday and looking slightly more favourable for Monday.