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Hourly Forecast
Daylight Hours
06:58
Sunrise
19:16
Sunset
Moon
Waxing Crescent
13:33
Moonrise
20:52
Moonset
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Weather in Merthyr Tydfil today, September 16, 2026
Merthyr Tydfil starts September 16, 2026 looking damp, with rain in the forecast and wetter spells likely at times. Waterproof kit is the safer call for early plans. Expect a grey start, with morning cloud around 74% by 10:00. Outdoor plans early on should not rely on bright skies.
Temperatures climb from an overnight low near 12°C toward a daytime high of about 16°C. Relative humidity sits between 65% and 91%, reaching its peak around 22:00. Winds stay light, near 4.9 km/h by 13:00, so the day feels still more than breezy.
The second half of the day still looks unsettled, with rain probability around 20% by 23:00. Dense cloud near 100% at 15:00 keeps the feel grey. Horizontal visibility sits around 31.8 km, briefly nearer 16.1 km. Daylight runs from 06:58 to 19:16, lasting 12 hours 18 minutes of sunlight today.
In short, treat September 16, 2026 in Merthyr Tydfil as a damp day: pack covers, watch the wetter hours, and expect a high near 16°C.
Frequently asked questions about weather in Merthyr Tydfil
How warm does it get in Merthyr Tydfil?
The warmest month in Merthyr Tydfil is July, with average high temperatures of 19°C. The average temperature during this period is around 16°C.
How cold does it get in Merthyr Tydfil?
The coldest month in Merthyr Tydfil is January, with average low temperatures of 2°C. The average temperature during this period is around 4°C.
What is the wettest time of year in Merthyr Tydfil?
The wettest month in Merthyr Tydfil is December, with an average of 140mm of precipitation.
What is the driest time of year in Merthyr Tydfil?
The driest month in Merthyr Tydfil is April, with an average of 75mm of precipitation.
