Environment Canada will issue a rainfall warning for the Lower Mainland ahead of an atmospheric river arriving soon.
Meteorologist Armel Castellan tells V.I.A. the storm will arrive Tuesday, Dec. 17 but isn't expected to bring as much moisture as other, more potent systems earlier this year.
"It won't be like October's event," he says, highlighting the storm that coincided with the B.C. Provincial Election on Oct. 19 and saw heavy rainfall cause widespread flooding and power outages across the region.
The rain is expected to start late Tuesday morning and pick up in the early afternoon, continuing past midnight and tapering off until 5 or 6 a.m. on Wednesday, Dec. 17, Castellan explains, characterizing the wet weather event as a "tight package."
Freezing levels will be lower at the beginning of the wet weather event and slowly rise to 2,500 meters. Local mountains should receive snow as the storm begins and then rainfall as temperatures warm up later in the day.
Metro Vancouver weather forecast
To meet rainfall warning criteria, at least 50 mm of precipitation must fall in 24 hours. Rainfall rates of 4 to 5 mm per hour are expected across most of Metro Vancouver, with some areas, such as the North Shore, seeing rates closer to 7 to 9 mm hourly.
Castellan says the Lower Mainland sees 30 to 40 atmospheric rivers annually and locals shouldn't feel anxious. Most of them bring much-needed moisture to the region and don't result in catastrophic flooding, despite notorious events such as the recent election day storm and the 2021 flooding.
This heavy rain isn't expected to last long or produce rainfall amounts similar to those events.
Wednesday's forecast includes a reprieve from the rainfall.
"We may even see some sunshine during the day," Castellan notes.
Thursday's forecast includes another pulse of wet weather midday but amounts won't meet rainfall warning criteria.
Heading into the weekend, more rainfall is expected to pick up on Friday night and continue through Saturday and Sunday.
"We're back to a lot of [storm] activity on the coast and we will get some heavy rain," Castellan says.
Stay up-to-date with hyperlocal forecasts across 50 neighbourhoods in the Lower Mainland with V.I.A.'s Weatherhood.
