Belfast Weather in September

With daytime temperatures of 17°C (63°F) and nighttime lows of 11°C (52°F), September in Belfast brings moderate temperatures during the day. Do keep in mind that quite a bit of rainfall is typical. Around 83 mm (3.3 in) falls on average.

Rainfall in Belfast in September

Records from the past 30 years suggest around 17 days of rain, with 83 mm (3.3 in) average for the month. This is a month with many wet days but modest rainfall totals, so showers are generally light and easy to manage.

Temperature in Belfast in September

Daytime highs in Belfast in September reach 17°C (63°F), with nights around 11°C (52°F). The summer season takes place during September. This creates a mild day-to-night pattern that is generally easy to manage with the right clothing. With overnight lows of 11°C (52°F), evenings can feel noticeably cooler than the daytime. An extra layer is a good idea, though the cool air makes for a good night's sleep.

Sunshine in Belfast in September

With about 109 hours of sunshine, the area enjoys a nice balance of sun and overcast, creating a pleasant environment.

Wind Speed in Belfast in September

September sees wind speeds averaging 4 m/s (8 knots). You'll experience variable conditions with moderate winds that create small waves on water and keep branches moving. Conditions range from light winds to moderate breezes throughout the month.

Average water temperature in September

With water at 13°C (55°F), it's on the cooler side. Keen swimmers won't be put off, but those who prefer warm water may find it less enjoyable.

If you prefer dry days with pleasant temperatures, July and August typically offer the best circumstances. If you're seeking pleasant, dry and sunny weather somewhere else in the world, our weather planner can help you explore other options.