A rainstorm may dump up to 30 mm of precipitation over the Lower Mainland and have a few surprises.
Environment Canada Meteorologist Chris Doyle told V.I.A. that locals should brace for a shift in temperatures and dry conditions starting Friday, June 14 when an upper-low-pressure system drops into the region from the Gulf of Alaska.
Before that happens, V.I.A's Trout Lake Weatherhood station shows a high of 21 C on Thursday with a mix of sun and cloud clearing in the late afternoon. Clouds are expected to roll in overnight with temperatures dropping to 10 C on Thursday (see slide two).
Friday's forecast includes a 30 per cent chance of showers in the morning with periods of rain commencing overnight. Temperatures will gradually decrease over the next few days.
On Saturday afternoon an upper-low system will bring cold, unstable air to the southwest B.C. coast. Showers, at times heavy, will be possible throughout the day with rainfall totalling 10 to 30 mm.
Metro Vancouver weather forecast includes thunderstorms
Embedded lightning is possible due to a warm surface and a "quite cold" air mass above it creating instability. Hail is also possible on Saturday afternoon, Doyle said.
"Saturday will be quite a bit cooler than what people expect," he noted. "Prepare for heavy rain and lightning."
Embedded lightning forms within the cloud deck when there isn't as much heat and energy.
Wet weather should continue through Sunday morning until the low-pressure system drops southeast to Washington in the afternoon.
Monday through Wednesday will see dry conditions and a gradual increase in daily temperatures. By Wednesday, the Trout Lake area in Vancouver could see temperatures climb back up to 22 C.
Doyle said the department's models aren't showing a conclusive forecast for next Thursday. However, the region may see a return to showers.
Stay up-to-date with hyperlocal forecasts across 50 neighbourhoods in the Lower Mainland with V.I.A.'s Weatherhood.
