Compare the mountain weather on Yr Wyddfa, Cadair Idris and Pen y Fan before choosing a day for the Welsh Three Peaks.
Every summit is shown side by side. The combined grade gives extra weight to the weakest forecast.
A poor day on the tops of Snowdon - Yr Wyddfa, with sleet or snow on the tops and burns likely to be in spate.
A poor day on the tops of Cadair Idris - Penygadair, with burns likely to be in spate and the summit in cloud for most of the day.
A poor day on the tops of Pen y Fan, with a blustery wind and cloud coming and going on the summit.
Weather data: Open-Meteo (CC BY 4.0). Adapted by Mountain Weather.
First-quarter moon
Moon up during darker hours17:00 GMT to 22:25 GMT
Window: 16 Nov, 17:00 GMT to 17 Nov, 08:00 GMT
First-quarter moon
Moon up during darker hours17:00 GMT to 22:25 GMT
Window: 16 Nov, 17:00 GMT to 17 Nov, 08:00 GMT
First-quarter moon
Moon up during darker hours17:00 GMT to 22:30 GMT
Window: 16 Nov, 17:00 GMT to 17 Nov, 08:00 GMT
Waxing gibbous moon
Moon up during darker hours17:00 GMT to 23:40 GMT
Window: 17 Nov, 17:00 GMT to 18 Nov, 08:00 GMT
Waxing gibbous moon
Moon up during darker hours17:00 GMT to 23:40 GMT
Window: 17 Nov, 17:00 GMT to 18 Nov, 08:00 GMT
Waxing gibbous moon
Moon up during darker hours17:00 GMT to 23:40 GMT
Window: 17 Nov, 17:00 GMT to 18 Nov, 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.
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