London vs Paris

Based on sunshine hours, rain days, comfortable temperatures, and humidity levels, Paris edges ahead as the better destination in September. Paris offers 9 hours of daily sunshine with only 8 rain days, while London sees 8 sunshine hours and 9 rain days.

London sits in the comfortable travel range at 19°C. Paris is also comfortable at 21°C.

For travelers who prioritize dry weather, Paris is the stronger choice in September. Paris receives 1 more hour of sunshine per day, which matters for sightseeing and outdoor activities.

London reaches an average high of 19°C (66°F) and drops to 11°C (52°F) at night during September. The daily temperature range is 8°C, meaning moderate variation throughout the day.

Paris averages 21°C (70°F) for the high and 12°C (54°F) for the low, with a daily range of 9°C. The 2°C difference is noticeable but not dramatic.

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

London receives approximately 48 mm of rainfall across 9 rain days during September. You can expect rain roughly every other day.

Paris sees 47 mm over 8 rain days. That makes Paris the drier option by 1 rain day and 1 mm of total precipitation.

Both cities share similar humidity levels at 65%.