Seattle vs Vancouver

Based on sunshine hours, rain days, comfortable temperatures, and humidity levels, Seattle edges ahead as the better destination in September. Seattle offers 10 hours of daily sunshine with only 8 rain days, while Vancouver sees 10 sunshine hours and 10 rain days.

Seattle sits in the comfortable travel range at 21°C. Vancouver is also comfortable at 20°C.

For travelers who prioritize dry weather, Seattle is the stronger choice in September.

Seattle reaches an average high of 21°C (70°F) and drops to 12°C (54°F) at night during September. The daily temperature range is 9°C, meaning moderate variation throughout the day.

Vancouver averages 20°C (68°F) for the high and 13°C (55°F) for the low, with a daily range of 7°C. The two cities feel quite similar in terms of temperature.

Both cities are in the Northern Hemisphere, so they share the same seasonal pattern in September.

Seattle receives approximately 64 mm of rainfall across 8 rain days during September. You can expect rain roughly every other day.

Vancouver sees 117 mm over 10 rain days. That makes Seattle the drier option by 2 rain days and 53 mm of total precipitation.

Both cities share similar humidity levels at 65%.