An Riabhachan weather forecast.

A fine day on An Riabhachan: summit wind broadly 10-25 mph, with gusts 25-35 mph early in the morning (fresh and blowy). Thunder watch from late afternoon into the evening: a small but credible risk is present. Watch for growing clouds and leave exposed tops if thunder develops. Much calmer lower down - generally 5-15 mph in the valley, rising towards the tops. Cloud base around 500–800 m in the morning, lifting to 1100–1400 m around midday and 1400–1700 m by late afternoon. The top is likely to drift in and out of cloud, with the best chance of a view from early morning into around midday. Little or no rain expected.

Forecast confidence: Rain is possible, but forecast models differ by about 11 hours on when it arrives.

A grey, cloudy day on An Riabhachan: summit wind broadly 10-25 mph, with gusts 25-35 mph early in the morning (strong winds). Much calmer lower down - generally 0-10 mph in the valley, rising towards the tops. Cloud base mostly around 400–700 m through daylight. Expect the top to stay in cloud for most or all of daylight, with no dependable break. Cloud is likely to hang lowest on northeastern slopes; the southwestern side should see somewhat higher bases and better breaks. Some rain is likely, with around 2-5 mm indicated; timing and local totals remain uncertain. Confidence moderate (forecast models agree on the walking impact of the wind) - the summit peak could reasonably be 16-27 mph, so treat the headline as mid-range.

Forecast confidence: Rain is possible, but forecast models differ by about 13 hours on when it arrives.

A grey, cloudy day on An Riabhachan: summit wind broadly 5-15 mph, with gusts 5-15 mph during the afternoon (a moderate breeze). Cloud base around 400-700 m in the morning, lifting to 600-900 m around midday. Expect the top to stay in cloud for most or all of daylight, with no dependable break. Little or no rain expected. Cloud base is the least certain part of this - the models are only moderately agreed, so it could sit a couple of hundred metres either way.

Forecast confidence: Thunderstorm timing is inherently uncertain and may shift by several hours.

A rough, clagged-in day on An Riabhachan: summit wind broadly 5-25 mph, with gusts 20-30 mph around midday (fresh and blowy). A meaningful thunderstorm risk is indicated from the morning into the evening. Avoid committing to exposed ridges if storms begin to build. Much calmer lower down - generally 0-10 mph in the valley, rising towards the tops. Cloud base around 400–700 m through the morning, lifting to 600–900 m by late afternoon. Expect the top to stay in cloud for most or all of daylight, with no dependable break. Cloud is likely to hang lowest on southern slopes; the northern side should see somewhat higher bases and better breaks. A persistently wet day is possible, with around 5-10 mm indicated; local totals could vary considerably.

Forecast confidence: Thunderstorm timing is inherently uncertain and may shift by several hours.

Cloud-free timing: Best around midday at about 75%; around 0% early and 0% later.

A grey, cloudy day on An Riabhachan: summit wind broadly 5-20 mph, with gusts 20-30 mph during the evening (fresh and blowy). A meaningful thunderstorm risk is indicated from the morning into the evening. Avoid committing to exposed ridges if storms begin to build. Cloud base around 400–700 m in the morning, then around 1200–1500 m around midday and 300–600 m by late afternoon. The top is likely to drift in and out of cloud, with the best chance of a view from midday into the afternoon. Some rain is likely, with around 5-10 mm indicated; timing and local totals remain uncertain. Confidence moderate (Summit wind could be roughly 9-28 mph, which changes how difficult exposed walking may feel) - the summit peak could reasonably be 9-28 mph, so treat the headline as mid-range.

Forecast confidence: Summit wind could be roughly 18-38 mph, which changes how difficult exposed walking may feel.

A rough, clagged-in day on An Riabhachan: summit wind broadly 20-35 mph, with gusts 35-45 mph around midday (strong winds). There could be a spate risk based on forecast rainfall. Burns and unbridged crossings may rise quickly. Most likely from around 00:00 until around 23:00. Much calmer lower down - generally 5-15 mph in the valley, rising towards the tops. Cloud base around 400-700 m in the morning, lifting to 700-1000 m around midday. Expect the top to stay in cloud for most or all of daylight, with no dependable break. Cloud is likely to hang lowest on northern slopes; the southern side should see somewhat higher bases and better breaks. A persistently wet day is possible, with around 5-10 mm indicated; local totals could vary considerably. Cold on top: air temperature broadly 2 to 6°C, feeling around -2 to 2°C in the wind - wrap up. Confidence moderate (Summit wind could be roughly 18-38 mph, which changes how difficult exposed walking may feel) - the summit peak could reasonably be 18-38 mph, so treat the headline as mid-range.