A wild day on the tops of Snowdon - Yr Wyddfa, with a real risk of thunderstorms and burns in severe spate.
Welsh Three Peaks weather forecast
Compare the mountain weather on Yr Wyddfa, Cadair Idris and Pen y Fan before choosing a day for the Welsh Three Peaks.
Forecast comparison
Every summit is shown side by side. The combined grade gives extra weight to the weakest forecast.
A wild day on the tops of Cadair Idris - Penygadair, with a real risk of thunderstorms and burns in severe spate.
A wild day on the tops of Pen y Fan, with severe winds and rain for much of the day.
Weather data: Open-Meteo (CC BY 4.0). Adapted by Mountain Weather.
Moon for your challenge
Night before your chosen day: Saturday 24 October 2026
Snowdon - Yr Wyddfa
Near-full moon
- Illuminated disc
- 98%
- Moonrise
- Outside this window
- Moonset
- 06:09 next morning GMT
Moon up during darker hours18:35 BST to 06:10 GMT next morning
Window: 24 Oct, 17:00 BST to 25 Oct, 08:00 GMT
Cadair Idris - Penygadair
Near-full moon
- Illuminated disc
- 98%
- Moonrise
- Outside this window
- Moonset
- 06:07 next morning GMT
Moon up during darker hours18:35 BST to 06:10 GMT next morning
Window: 24 Oct, 17:00 BST to 25 Oct, 08:00 GMT
Pen y Fan
Near-full moon
- Illuminated disc
- 98%
- Moonrise
- Outside this window
- Moonset
- 06:03 next morning GMT
Moon up during darker hours18:35 BST to 06:05 GMT next morning
Window: 24 Oct, 17:00 BST to 25 Oct, 08:00 GMT
Night beginning Sunday 25 October 2026
Snowdon - Yr Wyddfa
Near-full moon
- Illuminated disc
- 100%
- Moonrise
- Outside this window
- Moonset
- 07:39 next morning GMT
Moon up during darker hours17:35 GMT to 06:25 GMT next morning
Window: 25 Oct, 17:00 GMT to 26 Oct, 08:00 GMT
Cadair Idris - Penygadair
Near-full moon
- Illuminated disc
- 100%
- Moonrise
- Outside this window
- Moonset
- 07:37 next morning GMT
Moon up during darker hours17:35 GMT to 06:25 GMT next morning
Window: 25 Oct, 17:00 GMT to 26 Oct, 08:00 GMT
Pen y Fan
Near-full moon
- Illuminated disc
- 100%
- Moonrise
- Outside this window
- Moonset
- 07:31 next morning GMT
Moon up during darker hours17:35 GMT to 06:25 GMT next morning
Window: 25 Oct, 17:00 GMT to 26 Oct, 08:00 GMT
Approximate times in UK local time, for an open horizon. Moon-up periods are rounded to five minutes. Hills and cloud can hide the Moon. Illumination is the sunlit percentage of its disc, not how bright your route will be. Darker hours here begin after civil twilight. This almanac covers only the stated overnight window and does not change the weather grade. Take a headtorch and spare power regardless.
Planning the Welsh Three Peaks
The Welsh Three Peaks Challenge links three iconic mountains across north, mid and south Wales. Because the summits are widely separated, the forecast can vary far more than a single Wales-wide weather summary suggests.
Treat the combined grade as a quick comparison, then read each mountain row. A good forecast on one summit does not imply similar wind, cloud or rain on the other two.
Read Welsh Three Peaks route information