Is Belfast hot in September?
Days are typically cool at 16.9°C, while nights average 10°C.
United Kingdom · 1991–2020 normal
Belfast in
September.
Typical September weather in Belfast: 16.9°C by day, 10°C at night, 75 mm of rain over 11.5 wet days. These are measured 1991–2020 station normals, not a forecast.
Typical high16.9°C
Typical low10°C
Rain75 mm
Wet days11.5
In the year-round weather comparison, September scores 54 out of 100 (July leads the year at 64). Daylight is calculated as 12 h 38 from latitude 54.60°. Open-water sea temperature is 13.9°C (31 km from the place centre).
September at a glance
What is Belfast like in September?
Plain answers from the measured climate record—not a forecast or a promise about a particular trip.
Does it rain much?
The measured monthly average is 75 mm across about 12 wet days.
How much daylight is there?
There are about 12 h 38 between sunrise and sunset at mid-month, calculated from the place latitude.
Is September a good time to visit?
September ranks 4 of 12 in our weather comparison; July ranks first.
The evidence behind this page
One month,
from the same station.
- Place identity
- GeoNames 2655984
- NOAA station
- UKE00105877 · STORMONT CASTLE
- Station distance
- 6.3 km from the place centre
- Coverage
- Strong coverage · 29 usable years
- Important limit
- Historical climate is not a forecast. Nearby stations can miss mountains, coasts, and local microclimates.
Next step
Choose your month.
Then plan the details.
The weather comparison for Belfast is based on climate evidence, not payments from travel companies. Flight, accommodation and activity links will be clearly labelled when they are added; there are no booking offers on this page today.
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