Nanaimo sits in coastal British Columbia, where a mild oceanic climate brings Canada’s heaviest rainfall totals, driven largely by atmospheric rivers of moisture that arrive off the Pacific through autumn and winter.
On Vancouver Island, the city faces the same atmospheric river storm systems that affect the BC mainland coast. These atmospheric river events, including the catastrophic November 2021 storm that caused widespread flooding and landslides across the region, can drop extraordinary rainfall totals in just a few days, making radar an essential tool alongside Environment Canada’s official warnings. Learn more: Flash Flood Warning Signs on Radar · Open the full Rain Map