Is it safe to climb Ben Macdui today and tomorrow?

Today on Ben Macdui is rated Good and tomorrow Marginal, from the summit forecast. Summit forecast updated 19:11, 18 Oct. The reasons are below, followed by what the rating can't tell you.

Is it safe to climb Ben Macdui today?

Good Today Sunday 18 October

• Wind and gusts: Summit wind up to 6 mph, gusting 19 mph. That is under the Marginal line of 25 mph wind or 45 mph gusts.
• Rain: 0% chance of rain, about 0 mm in all.
• Cloud: Cloud cover averages 0% and humidity 76% at summit height. The forecast gives no cloud base height; the main peak page estimates one from the valley forecast.
• Temperature and wind chill: Up to 3°C at the summit, down to -3°C, feeling as cold as -7°C in the wind. Below freezing at the summit, so expect ice on rock and paths, especially early.
• Daylight: Sunrise 07:54, sunset 18:04: 10h 10m of daylight. The longest route listed here takes about 9h 0m there and back by Naismith's rule, before stops.

Is it safe to climb Ben Macdui tomorrow?

Marginal Tomorrow Monday 19 October

• Wind and gusts: Summit wind up to 35 mph, gusting 44 mph. That is past the Marginal line (wind 25 mph or gusts 45 mph): expect to be pushed about on ridges and the summit.
• Rain: 99% chance of rain, about 3.6 mm in all. A 60% chance or more makes the day Marginal on its own: wet rock is slippery and wet kit chills you faster.
• Cloud: Cloud cover averages 43% and humidity 90% at summit height. The forecast gives no cloud base height; the main peak page estimates one from the valley forecast.
• Temperature and wind chill: Up to 4°C at the summit, down to -2°C, feeling as cold as -7°C in the wind. Below freezing at the summit, so expect ice on rock and paths, especially early.
• Daylight: Sunrise 07:56, sunset 18:02: 10h 6m of daylight. The longest route listed here takes about 9h 0m there and back by Naismith's rule, before stops.

What the verdict covers, and what it doesn't

Peakify rates each day Good, Marginal or Poor from the forecast summit wind, gusts, chance of rain and wind chill. Wind of 40 mph or gusts of 65 mph make it Poor; wind of 25 mph, gusts of 45 mph, a 60% chance of rain or a feels-like temperature of -8°C or below make it Marginal. That is all it measures: the weather forecast at the summit.

It does not know your fitness or experience, whether you can navigate in cloud with a map and compass, or what you are carrying. It does not see the state of the path, river levels, snow and ice already on the ground, or how the forecast is changing during the day. A Good day can still go wrong if you start late, turn an ankle or lose the path in mist, and a Marginal day can be fine for an experienced party on the easiest route.

On any day, carry waterproofs, warm layers, a hat and gloves, food, water, a head torch and a charged phone, and know how you would navigate if the top is in cloud. Tell someone your route and when you expect to be down. In winter conditions you need an ice axe and crampons and the skill to use them, or a guide.

Route notes for Ben Macdui

Cairngorm ski centre via Cairn Lochan

From Cairngorm ski centre car park (Coire Cas). A path climbs past Coire an t-Sneachda to Cairn Lochan, then crosses the plateau south to the summit. Graded Hard: steeper, rougher or longer than the moderate routes, with more time on high, exposed ground. About 5h 45m there and back by Naismith's rule (10.4 km one way, 952 m of ascent).

Linn of Dee via Loch Etchachan

From Linn of Dee car park. A long walk to Derry Lodge and up Glen Derry, then a climb past Loch Etchachan to the summit. Graded Hard: steeper, rougher or longer than the moderate routes, with more time on high, exposed ground. About 9h 0m there and back by Naismith's rule (17.5 km one way, 1,221 m of ascent).

Full distances, ascent and times are on the Ben Macdui routes page.

In an emergency

Call 999, ask for the police and then mountain rescue. Mountain rescue teams in the UK are volunteers called out through the police. Give your location (a grid reference from a map or phone app if you can), what has happened, how many are in your group and your phone number, then keep the phone free. If you have no signal, try to move to higher ground or text 999; you need to have registered your phone with the emergencySMS service before for a text to work.

Questions about Ben Macdui

Is it safe to climb Ben Macdui today?

Today, Sunday 18 October: clear sky, up to 3°C at the summit, feeling as cold as -7°C, summit wind 6 mph gusting 19 mph, 0% chance of rain. Rated Good. The rating covers the summit weather only; your route, kit and experience matter as much.

Is it safe to climb Ben Macdui tomorrow?

Tomorrow, Monday 19 October: moderate drizzle, up to 4°C at the summit, feeling as cold as -7°C, summit wind 35 mph gusting 44 mph, 99% chance of rain. Rated Marginal.

How does Peakify decide whether Ben Macdui is safe to climb?

Peakify rates each day Good, Marginal or Poor from the forecast summit wind, gusts, chance of rain and wind chill. Wind of 40 mph or gusts of 65 mph make it Poor; wind of 25 mph, gusts of 45 mph, a 60% chance of rain or a feels-like temperature of -8°C or below make it Marginal. It does not judge your fitness, kit, navigation or the state of the path.

Who do I call in an emergency on Ben Macdui?

Call 999, ask for the police and then mountain rescue. Give your location (a grid reference if you can), what happened and how many are in your group. Stay with the casualty and keep them warm.