Compare all 15 summits over 3,000 feet in Eryri before committing to this long and serious mountain challenge.
Every summit is shown side by side. The combined grade gives extra weight to the weakest forecast.
A wild day on the tops of Snowdon - Yr Wyddfa, with very strong, gusty winds and burns likely to be in spate.
A wild day on the tops of Crib y Ddysgl, with very strong, gusty winds and burns likely to be in spate.
A poor day on the tops of Crib Goch, with very strong, gusty winds and burns likely to be in spate.
A poor day on the tops of Elidir Fawr, with very strong, gusty winds and burns likely to be in spate.
A poor day on the tops of Y Garn, with very strong, gusty winds and burns likely to be in spate.
A poor day on the tops of Glyder Fawr, with very strong, gusty winds and burns likely to be in spate.
A poor day on the tops of Glyder Fach, with very strong, gusty winds and burns likely to be in spate.
A poor day on the tops of Tryfan, with very strong, gusty winds and drizzle for much of the day.
A poor day on the tops of Pen yr Ole Wen, with very strong, gusty winds and drizzle for much of the day.
A poor day on the tops of Carnedd Dafydd, with very strong, gusty winds and drizzle for much of the day.
A poor day on the tops of Carnedd Llewelyn, with very strong, gusty winds and drizzle for much of the day.
A poor day on the tops of Yr Elen, with very strong, gusty winds and drizzle for much of the day.
A poor day on the tops of Foel Grach, with very strong, gusty winds and drizzle for much of the day.
A poor day on the tops of Garnedd Uchaf, with strong, gusty winds and drizzle for much of the day.
A poor day on the tops of Foel-fras, with very strong, gusty winds and drizzle for much of the day.
Weather data: Open-Meteo (CC BY 4.0). Adapted by Mountain Weather.
Area reference: Glyder Fawr. Local mountain horizons will vary.
Near-full moon
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
Area reference: Glyder Fawr. Local mountain horizons will vary.
Near-full moon
Moon up during darker hours17:35 GMT to 06:30 GMT next morning
Window: 26 Oct, 17:00 GMT to 27 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.
The Welsh 3000s crosses the Yr Wyddfa, Glyderau and Carneddau ranges, taking in 15 summits above 3,000 feet. Its length, exposed scrambling and repeated high ground make a single valley forecast inadequate for choosing a day.
The combined grade is deliberately conservative and gives extra weight to the weakest summit. Review every row, especially Crib Goch and Tryfan, and use the full peak pages for timing and hazard detail.
Read BMC Welsh 3000s guide