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Today on Snowdon

Live · Open-Meteo

Prepared walker day

Manageable summit conditions — overcast at 11°C, valley 18°C, 18 mph gusts. Prepared walkers can proceed with standard mountain caution and kit.

Summit observed 21 Sept, 15:00 · just nowOpen-Meteo · free weather API · 15-min cache

Live readings

Open-Meteo · just now

Summit temp

11°C

~1026 m elevation

Valley temp

18°C

Llanberis · ~119 m

Summit gusts

18mph

Manageable

Conditions

Overcast

100% cloud

Summit data: 1026 m elevation model (Yr Wyddfa) · Valley data: 119 m (Llanberis) · Source: Open-Meteo (free, no key required)


Today, tomorrow, and the next three days

Open-Meteo forecast · just now

Best window in this short range

Tomorrow

Tomorrow is the cleanest summit-fit day in this three-day window.

The short-range trend looks rougher and less settled as the window goes on.

If you need to choose inside this window, tomorrow is the better bet. Wed carries the roughest combination of wind, wet ground, or low cloud.

This is a bounded planning outlook from Open-Meteo daily forecast data, not a guarantee of upper-mountain conditions.

Today

Mon 21 Sept

More marginal summit day

Drizzle

Wind looks more manageable than on the rougher days in this short window, with summit gusts around 23 mph. This looks like the drier part of the window, even though a stray shower still cannot be ruled out. Upper cloud is likely to sit in for long stretches. Temperature is less of a limiting factor than wind and wet ground.

Summit range
6 to 12°C
Valley range
12 to 18°C
Summit gusts
23 mph max
Precipitation
Lower precipitation signal · 14% chance

Mean cloud ~86% · upper mountain likely murkier

Better for prepared walkers who are happy to keep ambition controlled and turn around early if the mountain feels worse than forecast.

Still a forecast rather than a guarantee — check the live page before leaving the valley.

Tomorrow

Tue 22 Sept

Better summit window

Drizzle

Wind looks more manageable than on the rougher days in this short window, with summit gusts around 15 mph. Showers are still in the picture, so expect mixed rather than fully dry ground. Cloud looks mixed rather than fully clear. Temperature is less of a limiting factor than wind and wet ground.

Summit range
9 to 12°C
Valley range
15 to 19°C
Summit gusts
15 mph max
Precipitation
41% precipitation signal · mixed showers possible

Mean cloud ~61% · mixed tops

Best of this short window for a summit plan, assuming the day-of live picture still agrees.

Useful for tomorrow-shape planning, but still worth rechecking on the day.

Wed

Wed 23 Sept

Poorer summit fit

Rain

The top still looks exposed, with gusts around 38 mph shaping the day. The forecast stays wet enough to slow the day down, with around 12.0 mm and a 89% precipitation signal. Cloud looks mixed rather than fully clear. It still looks cold on top, even if the valley start feels more forgiving.

Summit range
1 to 9°C
Valley range
8 to 15°C
Summit gusts
38 mph max
Precipitation
12.0 mm forecast · 89% precipitation signal

Mean cloud ~62% · mixed tops

Stronger fit for a lower-commitment plan, a railway / village day, or waiting for a cleaner window.

Confidence softens further out, so treat this as a day-shape guide rather than a promise.


What today means

Derived from live data
Best fit for
Prepared walkers with route judgement, mountain kit, and map competence.
Poor fit for
Underprepared groups treating valley conditions as summit conditions.
Main limiting factor
Summit cloud / low visibility.
Planning consequence
Dry conditions expected. Standard mountain weather caution still applies — conditions can change faster than forecasts at this elevation.

Today by visitor type

First-time visitor
Good day for a first summit attempt via the more forgiving branches if you start conservatively and carry proper kit.
Prepared walker
Conditions are manageable across the main route families, so choose based on capability, visibility, and preferred start point.
Railway / non-hiker
Hiking conditions are workable today, but the railway remains a valid mixed-group or non-hiker option if that better suits the day.
Travelling without a car
Transport-linked trailheads still make sense today, so compare the cleaner access branches before you set off.

Read the mountain today

Interpreted from live data

Wind

18 mph gusts

Wind is not a primary concern today (18 mph gusts). Standard mountain caution applies on open ridges, but conditions are manageable.

Common mistake: valley calm does not mean exposed ridges are manageable.

How it changes the day: strong summit wind increases energy cost, reduces margin for error at junctions, and accelerates hypothermia risk.

Cloud / visibility

100% cloud cover

Summit likely in cloud. Visibility may collapse sharply above 700–900m — the exact height depends on cloud base, which can shift quickly.

Common mistake: a clear start in Llanberis does not guarantee visibility at upper-route junctions.

How it changes the day: low cloud raises navigation demand and makes turnaround decisions harder.

Precipitation

Overcast

Dry conditions expected. Standard mountain weather caution still applies — conditions can change faster than forecasts at this elevation.

Common mistake: light showers at low elevation often imply worse conditions above 600 m.

How it changes the day: wet rock and wintry surfaces slow pace, increase slip risk, and raise kit requirements.

Summit vs valley

Valley 18°C / Summit 11°C

Moderate summit-valley difference (7°C). Valley 18°C, summit 11°C. The upper mountain is noticeably colder and more exposed than the valley suggests.

Why it changes the day: kit, timing, confidence, and route choice all shift with altitude. The gap between conditions at the car park and at the summit is often larger than it looks from the valley.


Ground conditions and operator context

Manual · Operator record: 24 March 2026 at 16:10 UTC

Operator record is the bundled fallback — live weather data above is more current.

Ground reports remain winter-focused and should only be treated as an additional support layer during colder periods.

Underfoot conditions matter as much as forecast headlines. Wet slabs, iced upper sections, and reduced visibility increase error cost at route junctions and steep traverses.

Practical rule: if upper-mountain confidence is sliding, downgrade early or switch to railway or non-hiker planning before travel momentum commits to a poor decision.


What kind of day is this?

Casual first-time summit

Low-demand day where casual first-timers can proceed safely.

Prepared walker day

Good conditions for walkers with mountain kit and route judgement.

Railway / non-hiker

Conditions push groups toward the railway or non-hiker branch.

Downgrade / delay

Summit ambition should be reduced or delayed today.


Next planning move

Conditions understood — now complete operational checks and pick a start point.