Sail weather forecast.

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

Cloud-free timing: Cloudy early, clearing later.

A mixed day on Sail: summit wind broadly 15-35 mph, with gusts 35-45 mph early in the morning (gale-force winds). Thunderstorms are a significant hazard from the morning into the evening. Exposed summits and ridges are a poor choice while storms are nearby. Much calmer lower down - generally 0-10 mph in the valley, rising towards the tops. Any cloud sits well above the tops (base 700-1500 m) - clear summits. Cloud is likely to hang lowest on southeastern slopes; the northwestern 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 24-32 mph, so treat the headline as mid-range.

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

Cloud-free timing: Around 0% early, improving to around 60% later.

A rough, clagged-in day on Sail: summit wind broadly 20-35 mph, with gusts 35-45 mph during the afternoon (gale-force winds). A meaningful thunderstorm risk is indicated from around midday into the evening. Avoid committing to exposed ridges if storms begin to build. There could be a spate risk based on forecast rainfall. Burns and unbridged crossings may rise quickly. Most likely from around 18:00 until around 02:00 the following day. 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 700–1000 m around midday and 900–1200 m by late afternoon. The top is likely to drift in and out of cloud, with the best chance of a view during the afternoon. Cloud is likely to hang lowest on eastern slopes; the western 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. Confidence moderate (forecast models agree on the walking impact of the wind) - the summit peak could reasonably be 24-33 mph, so treat the headline as mid-range. 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 grey, cloudy day on Sail: summit wind broadly 15-30 mph, with gusts 30-40 mph during the morning (strong winds). A meaningful thunderstorm risk is indicated from early morning into around midday. Avoid committing to exposed ridges if storms begin to build. 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 western slopes; the eastern 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 17-29 mph, so treat the headline as mid-range.

Forecast confidence: Rain is possible, but forecast models differ by about 9 hours on when it arrives.

A grey, cloudy day on Sail: summit wind broadly 10-25 mph, with gusts 15-25 mph early in the morning (fresh and blowy). 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 southwestern slopes; the northeastern 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.

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

Cloud-free timing: Around 0% early, improving to around 20% later.

A grey, cloudy day on Sail: summit wind broadly 15-30 mph, with gusts 30-40 mph during the evening (strong winds). A meaningful thunderstorm risk is indicated from early morning into the evening. Avoid committing to exposed ridges if storms begin to build. Much calmer lower down - generally 5-15 mph in the valley, rising towards the tops. Cloud base around 400–700 m in the morning, then around 900–1200 m around midday and 600–900 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. Cloud is likely to hang lowest on southwestern slopes; the northeastern 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 (Summit wind could be roughly 18-37 mph, which changes how difficult exposed walking may feel) - the summit peak could reasonably be 18-37 mph, so treat the headline as mid-range.

Forecast confidence: A low thunderstorm risk remains difficult to time precisely.

Cloud-free timing: Around 0% early, improving to around 100% later.

A wild day on Sail: summit wind broadly 40-55 mph, with gusts 65-75 mph during the afternoon (storm-force winds). Thunderstorms are possible from early morning into the afternoon. Keep an escape route from exposed ridges and descend if thunder develops. 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 15-25 mph in the valley, rising towards the tops. Cloud base around 400–700 m in the morning, lifting to 800–1100 m around midday and 1300–1600 m by late afternoon. The top is likely to drift in and out of cloud, with the best chance of a view from around midday into the evening. Cloud is likely to hang lowest on western slopes; the eastern side should see somewhat higher bases and better breaks. A persistently wet day is possible, with around 10-20 mm indicated; local totals could vary considerably. Cold on top: air temperature broadly 6 to 10°C, feeling around -2 to 2°C in the wind - wrap up. Low confidence (Summit wind could be roughly 40-61 mph, which changes how difficult exposed walking may feel) - the summit peak could be anywhere from 40 to 61 mph; check again nearer the time.

Forecast confidence: Summit wind could be roughly 40-58 mph, which changes how difficult exposed walking may feel.

Cloud-free timing: Around 33% early, falling to around 0% later.

A rough, clagged-in day on Sail: summit wind broadly 35-50 mph, with gusts 60-70 mph around midday (storm-force winds). The ground is likely to be wet after recent rain. There could be a spate risk based on forecast rainfall. Burns and unbridged crossings may rise quickly. Most likely from around 08:00 until around 03:00 the following day. Much calmer lower down - generally 15-25 mph in the valley, rising towards the tops. Cloud base around 700-1000 m in the morning, lowering to 500-800 m around midday. Expect clag for much of the day, though a brief clearance is possible early in the morning. Cloud is likely to hang lowest on western slopes; the eastern side should see somewhat higher bases and better breaks. A persistently wet day is possible, with around 10-20 mm indicated; local totals could vary considerably. Cold on top: air temperature broadly 4 to 8°C, feeling around -4 to 0°C in the wind - wrap up. Low confidence (Summit wind could be roughly 40-58 mph, which changes how difficult exposed walking may feel) - the summit peak could be anywhere from 40 to 58 mph; check again nearer the time.