Carnedd y Filiast weather forecast.

Cloud-free timing: Cloudy early, clearing later.

A mixed day on Carnedd y Filiast: summit wind broadly 15-30 mph, with gusts 35-45 mph during the evening (strong winds). 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 1500–1800 m around midday and 2000–2300 m by late afternoon. Summit cloud should lift later, bringing a better chance of clear views. Little or no rain expected.

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

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

A mixed day on Carnedd y Filiast: summit wind broadly 5-25 mph, with gusts 20-30 mph early in the morning (fresh and blowy). Thunderstorms are a significant hazard from around midday 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. Cloud base around 500–800 m through the morning, lifting to 1100–1400 m by late afternoon. The top is likely to drift in and out of cloud, with the best chance of a view from late afternoon into the evening. 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.

A rough, clagged-in day on Carnedd y Filiast: summit wind broadly 10-25 mph, with gusts 20-30 mph around midday (fresh and blowy). Thunderstorms are a significant hazard from the morning into the evening. Exposed summits and ridges are a poor choice while storms are nearby. 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. 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 eastern slopes; the western 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.

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

Cloud-free timing: Around 0% early, improving to around 80% later.

A grey, cloudy day on Carnedd y Filiast: summit wind broadly 10-25 mph, with gusts 20-30 mph during the afternoon (fresh and blowy). A meaningful thunderstorm risk is indicated from early morning into the evening. Avoid committing to exposed ridges if storms begin to build. 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 00:00 until around 17:00. Cloud base around 400–700 m through the morning, lifting to 700–1000 m by late afternoon. The top is likely to drift in and out of cloud, with the best chance of a view from late afternoon into the evening. Cloud is likely to hang lowest on northwestern slopes; the southeastern side should see somewhat higher bases and better breaks. Some rain is likely, with around 5-10 mm indicated; timing and local totals remain uncertain.

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

A rough, clagged-in day on Carnedd y Filiast: summit wind broadly 10-25 mph, with gusts 20-30 mph early in the morning (fresh and blowy). A meaningful thunderstorm risk is indicated from around midday into the evening. Avoid committing to exposed ridges if storms begin to build. 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 23:00. 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. 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: Around 0% early, improving to around 40% later.

A mixed day on Carnedd y Filiast: summit wind broadly 15-30 mph, with gusts 30-40 mph during the evening (strong winds). Thunderstorms are a significant hazard from early morning into the evening. Exposed summits and ridges are a poor choice while storms are nearby. The ground is likely to be wet after recent rain. 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 400–700 m by late afternoon. The top is likely to drift in and out of cloud, with the best chance of a view from the morning 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 5-10 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 20-32 mph, so treat the headline as mid-range.

Forecast confidence: Summit wind could be roughly 20-36 mph, which changes how difficult exposed walking may feel.

A mixed day on Carnedd y Filiast: summit wind broadly 20-35 mph, with gusts 35-45 mph during the afternoon (gale-force winds). The ground is likely to be wet after recent rain. Much calmer lower down - generally 10-20 mph in the valley, rising towards the tops. Any cloud sits well above the tops (base 900-1200 m) - clear summits. 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 (Summit wind could be roughly 20-36 mph, which changes how difficult exposed walking may feel) - the summit peak could reasonably be 20-36 mph, so treat the headline as mid-range.