How Wind & Air Masses Shape Vancouver's Climate

Vancouver's coastal location creates a dynamic interplay of air masses:

1. Pacific Maritime Air (Dominant)

Moist, mild onshore flow → cool wet winters (Jan avg 4°C), warm dry summers (Jul avg 18°C). 1,200–2,000 mm annual rain.

2. Chinook Winds (Foehn)

Descending leeward of Coast Mountains → rapid warming (10–15°C rise in hours), snow melt, dry air. Winter phenomenon.

3. Fraser Valley Outflow (Arctic Air)

Cold, dense air funnels SW down Fraser Canyon → clear, frigid spells (–10°C possible). Winter, high pressure interior.

4. Summer Sea Breezes

Daytime land heating → onshore flow from Strait of Georgia → natural AC.

5. Pacific Storm Winds

Atmospheric rivers / bomb cyclones → extreme rain, gales (Oct–Mar). Cause flooding, tree fall, power outages.

Net result: Canada's mildest major city, but with dramatic episodic swings.