Troedyrhiw Pressure & Humidity
Merthyr Tydfil — Barometric Trends
Troedyrhiw Pressure & Humidity Outlook
Across Troedyrhiw today, the barometer is near 993 mb, well on the low side, with humidity high enough to give the air a damp edge. That raises the chance of a more changeable spell at times, even with quieter windows in between. With a wide spread in values, the background feel can swing between steadier and more mixed spells. A gentle rise later on would slightly favour more settled spells.
Through the period, pressure is projected to run between 996 mb and 1024 mb across the outlook period. Pressure trends higher through the coming days, favouring quieter spells at times. Humidity looks generally high, which can help low cloud to linger in calmer spells.
Current Readings
Pressure
Humidity
Dew Point
Today’s Hourly Humidity
Today’s Hourly Pressure
14-Day Trends
Humidity Chart
Pressure Chart
Forecast context and reference links
To plan confidently, separate what is likely from what is uncertain. Use the supporting guides to understand why the outlook is behaving the way it is for Troedyrhiw.
- England Climate for regional patterns and seasonal tendencies.
- UK Climate Overview for a national baseline and how regions compare.
- England for location browsing and regional navigation.
How to interpret confidence
For how forecast reliability changes with lead time, see Forecast Confidence. For transparency on how WeatherEngland sources and updates data, see Methodology.
Background guides
- UK Weather Patterns
- UK Seasonal Weather
- UK Weather Hazards
- UK Weather Safety
- UK Jet Stream
- UK Microclimates
Glossary support
Start with the Weather Glossary. Useful terms for this page include Isobar, Pressure Gradient, Relative Humidity, Dew Point, Anticyclone, and Depression.
FAQ
What is the air pressure in Troedyrhiw today?
Atmospheric pressure in Troedyrhiw is currently around 993 mb. Think of it as the background state of the atmosphere; the timing of cloud and rain still depends on the next weather system. Humidity is near 97%, so the air is close to saturation — conditions where low cloud or reduced visibility can become more likely if winds ease, especially overnight. As the period goes on, the barometer tends to lift, supporting a more settled background pattern at times.
What counts as high or low pressure in the UK?
As a rough guide, the low 1020s (around 1020 mb–1024 mb) tends to be a more settled signal, while the low 1000s (around 1000 mb–1004 mb) more often points to Atlantic influence. The overall pattern matters more than any single reading.
How does pressure affect wind in Troedyrhiw?
Wind strength is driven mainly by the pressure gradient — how quickly pressure changes over distance. Tightly packed isobars usually mean stronger winds; a slack pattern often allows lighter winds, regardless of whether the headline pressure is high or low.
Does low pressure always mean rain in Troedyrhiw?
No. Low pressure increases the chance of changeable weather, but the wettest rain bands can miss your area entirely depending on where fronts set up.
What does humidity mean for comfort in Troedyrhiw?
It reflects how much moisture the air is holding compared with its maximum. Higher values can favour haze or low cloud, especially when winds are light. Humidity is frequently elevated through the period, which can keep the air feeling damp and occasionally reduce visibility in lighter winds.