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Ystradgynlais Weather

HomeWeatherYstradgynlais Weather

Live forecasts update automatically; written guidance last reviewed 20 June 2026 by the Culture Observer weather desk. Data from national met services via Open-Meteo.

☀️14°C
Clear skyYstradgynlaisFeels like 13° · Wind 2 km/h · Humidity 78%
UV 5 ModerateSunrise 05:50Sunset 20:50
Today☁️25°13°💧2%
Mon☁️24°13°💧0%
Tue26°13°💧0%
Wed30°14°💧0%
Thu☀️29°16°💧6%
Fri25°14°💧16%
Sat☁️23°13°💧8%

Live data from Open-Meteo · updates automatically ·

The live forecast above shows the current conditions for Ystradgynlais. For a short stay, May–September offers the mildest weather, though rain is possible any month. Pack layers and a waterproof jacket; school holidays bring higher accommodation demand in the Brecon Beacons area.

When is the best time to visit Ystradgynlais?

Late spring (May–June) and early autumn (September) give the most reliable combination of dry spells and comfortable temperatures for walking the nearby Swansea Valley or Dan-yr-Ogof caves. July–August is warmest but busier with families during school holidays.

What should I pack for a trip?

A waterproof shell and sturdy footwear are essential year-round. In winter (November–February) add thermal layers, a hat and gloves. Summer days can reach 20°C, so light trousers and a fleece work well. Check the live forecast above before you leave.

LocationPowys, Wales, SA9 1AA
Elevation~100m above sea level
Average annual rainfall~1,400mm
Nearest major citySwansea (20 miles south)
Is Ystradgynlais prone to flooding?

The town lies near the River Tawe and can see localised flooding after prolonged heavy rain. Check the live forecast above and any flood warnings from Natural Resources Wales before planning riverside walks.

Does the weather affect local attractions?

Yes – Dan-yr-Ogof Showcaves are open year-round but outdoor trails may close in icy or stormy weather. The Brecon Mountain Railway also runs reduced services in winter. Always confirm ahead via the attraction’s website.

Where can I find reliable forecasts for Ystradgynlais?

The live forecast above is from BBC Weather. For detailed mountain conditions, use the Met Office’s specific site: met office weather ystradgynlais. Local bbc news bulletins also cover severe weather warnings for the area.

For other parts of the UK, see our UK weather hub or check the 10 Day Weather Forecast UK. Travelers heading to the Welsh valleys may also find our Bristol Weather page useful for planning a route via the M4.