Weather in Belfast - 14-day forecast

Detailed weather forecast for Belfast, Ireland: daytime and night temperature, rain, sunrise and sunset - today and for the next two weeks.

Forecast for the next days in Belfast

today☁️ 18°💧 0.1 mm

Sun🌧️ 19°💧 1 mm

Mon☁️ 17°💧 9.4 mm

Tue🌧️ 12°💧 1.8 mm

Wed🌧️ 16°💧 1.3 mm

Thu🌧️ 19°💧 1 mm

Fri🌧️ 16°💧 0.9 mm

Sat☁️ 18°💧 2.7 mm

Forecast vs 1991-2020 climate normal

How does the current forecast compare with normal?

We compare the coming days with weather usually observed at this time of year.

NASA POWER

Sunday 6 Sept in Belfast, the forecast high is 19°C. Typical daytime temperatures at this time of year range from 15°C to 17°C, so it will be exceptionally warm. It is warmer than 97% of similar days.

Saturday 5 Sept

18°Cexceptionally warm

usually 15°C–17°C

warmer than 92% of similar days

night: exceptionally warm rain: less rain than usual wind: typical

Sunday 6 Sept

19°Cexceptionally warm

usually 15°C–17°C

warmer than 97% of similar days

night: exceptionally warm rain: typical rainfall wind: typical

Monday 7 Sept

17°Cwarmer than usual

usually 15°C–17°C

warmer than 80% of similar days

night: near normal rain: exceptionally wet wind: typical

Tuesday 8 Sept

12°Cexceptionally cool

usually 14°C–17°C

cooler than 97% of similar days

night: near normal rain: typical rainfall wind: typical

Wednesday 9 Sept

16°Cnear normal

usually 14°C–17°C

night: near normal rain: typical rainfall wind: lighter than usual

Thursday 10 Sept

19°Cexceptionally warm

usually 14°C–17°C

warmer than 97% of similar days

night: warmer than usual rain: typical rainfall wind: typical

Friday 11 Sept

16°Cnear normal

usually 14°C–17°C

night: near normal rain: typical rainfall wind: typical

How warm was this week in previous years?

Each bar shows the average daily high during the same 7-day period in each year.

swipe to see more years →

cooler yearstypical rangewarmer years2026 forecastcurrent forecast

From 1981 to 2025, the 5-11 Sept period averaged 16°C by day. The coolest year was 1986 (13°C) and the warmest was 2023 (20°C). The current forecast averages 17°C - higher than in 89% of historical years.

Historical reference: NASA POWER daily gridded data (MERRA-2), the 1991-2020 normal and a +/- 7-day calendar window. The typical range is the 20th-80th percentile. This is not a city weather-station reading and does not change the current forecast. NASA POWER Daily API.

Weather warnings - Belfast

No active weather warnings for Belfast (region: Fair-Belfast). The national weather service is not forecasting dangerous conditions.

14-day forecast - Belfast

Belfast - 14-day weather forecast infographic

Belfast 30 & 45-day weather - long-range outlook

Next 16 days · forecast

17°

around 12° at night · days with rain: 8

Weeks 3-4 · avg for September

17°

around 11° at night · rain chance 50%

Weeks 5-7 · avg for October

14°

around 9° at night · rain chance 57%

The 30 & 45-day outlook for Belfast: the next 16 days are a numerical forecast updated daily - on average 17° by day and 12° at night. Further out we rely on multi-year climate averages: around 17° in September, and about 14° in October. Forecasts beyond two weeks are indicative only.

Day-by-day forecast for Belfast

Saturday5 September 2026

☁️18°overcast clouds

sunrise 06:37 · sunset 20:07 · night 15° · evening 16° · rain 0.1 mm · humidity 58% · wind 7 m/s · clouds 91%

Sunday6 September 2026

🌧️19°light rain

sunrise 06:39 · sunset 20:04 · night 16° · evening 19° · rain 0.95 mm · humidity 73% · wind 7 m/s · clouds 99%

Monday7 September 2026

☁️17°overcast clouds

sunrise 06:41 · sunset 20:02 · night 11° · evening 14° · rain 9.44 mm · humidity 55% · wind 9 m/s · clouds 97%

Tuesday8 September 2026

🌧️12°light rain

sunrise 06:43 · sunset 19:59 · night 11° · evening 13° · rain 1.78 mm · humidity 77% · wind 9 m/s · clouds 83%

Wednesday9 September 2026

🌧️16°light rain

sunrise 06:45 · sunset 19:56 · night 11° · evening 13° · rain 1.33 mm · humidity 57% · wind 6 m/s · clouds 47%

Thursday10 September 2026

🌧️19°light rain

sunrise 06:47 · sunset 19:54 · night 13° · evening 16° · rain 0.99 mm · humidity 68% · wind 7 m/s · clouds 100%

Friday11 September 2026

🌧️16°light rain

sunrise 06:48 · sunset 19:51 · night 11° · evening 14° · rain 0.87 mm · humidity 63% · wind 8 m/s · clouds 66%

Saturday12 September 2026

☁️18°broken clouds

sunrise 06:50 · sunset 19:49 · night 10° · evening 14° · rain 2.7 mm · humidity 57% · wind 3 m/s · clouds 63%

Sunday13 September 2026

☀️19°clear sky

sunrise 06:52 · sunset 19:46 · night 11° · evening 16° · rain 1.02 mm · humidity 57% · wind 2 m/s · clouds 6%

Monday14 September 2026

🌤️19°a few clouds

sunrise 06:54 · sunset 19:44 · night 12° · evening 17° · rain 0.3 mm · humidity 61% · wind 5 m/s · clouds 14%

Tuesday15 September 2026

🌧️17°light rain

sunrise 06:56 · sunset 19:41 · night 12° · evening 16° · rain 0.15 mm · humidity 77% · wind 6 m/s · clouds 91%

Wednesday16 September 2026

🌧️15°light rain

sunrise 06:57 · sunset 19:39 · night 10° · evening 14° · rain 1.44 mm · humidity 84% · wind 7 m/s · clouds 88%

Thursday17 September 2026

🌧️17°moderate rain

sunrise 06:59 · sunset 19:36 · night 14° · evening 14° · rain 6.3 mm · humidity 58% · wind 6 m/s · clouds 96%

Friday18 September 2026

🌧️17°heavy rain

sunrise 07:01 · sunset 19:34 · night 13° · evening 15° · rain 16.8 mm · humidity 93% · wind 8 m/s · clouds 97%

Saturday19 September 2026

☁️16°overcast clouds

sunrise 07:03 · sunset 19:31 · night 11° · evening 14° · rain 0.62 mm · humidity 70% · wind 3 m/s · clouds 100%

Sunday20 September 2026

☀️18°clear sky

sunrise 07:05 · sunset 19:29 · night 15° · evening 15° · humidity 62% · wind 3 m/s

UV index in Belfast - is it safe to sunbathe?

Today the UV index in Belfast is 2 (low). You can safely stay outside. Sunscreen only matters for very long exposure.

Belfast weather through the year

Warmest, driest months on average: May, June, July, August.

Upcoming public holidays in Ireland: October Holiday — 26 October · Christmas Day — 25 December · St. Stephen's Day — 26 December.

Nearby and related places

SwordsDublinCorkAthloneWaterfordGalway

FAQ - Belfast weather

What is the weather like in Belfast today?

Today it is about 18° during the day and 15° at night, overcast clouds.

How far ahead can I check the forecast for Belfast?

This page shows a detailed 14-day forecast plus the long-term monthly climate, so you can plan both a short trip and a holiday months ahead.