Pen y Fan Weather Forecast: 14 Day, Radar, Hourly & More

Pen y Fan’s weather is notoriously changeable, and this guide provides the essential forecasts, radar data, and historical records to plan a safe hike.

Average July high temperature: 18°C ·
Average January low temperature: 1°C ·
Average annual rainfall: 2000 mm ·
Record high temperature: 30°C ·
Average wind speed at summit: 20 mph

Five essential facts about Pen y Fan’s weather and geography stand out:

Pen y Fan weather 14 day

Met Office 14-day forecast

• The Met Office (UK national weather service) provides a dedicated Pen Y Fan page with a 14-day outlook, including daily highs/lows, wind speed/direction, and probability of precipitation.
• The forecast updates several times a day and includes a “next hour” view for immediate planning.

Netweather 10-day vs 14-day

• Netweather (specialist UK weather site) offers an hour-by-hour forecast for Pen-y-fan covering today and the next 14 days, with a focus on precipitation and wind.
• Some providers like meteoblue (Swiss weather model specialist) limit their free tier to 10 days, making 14-day data a premium feature.

Accuracy of long-range forecasts

• Beyond 7 days, forecast models diverge. The The Weather Outlook (UK weather aggregator) shows 16-day views but notes decreasing reliability after day 7.
• For mountain locations like Pen y Fan, day-to-day variability means that a 14-day high/low is useful for trend awareness but not for precise hike timing.

What this means: The 14-day forecast is a directional guide, not a precise schedule for your hike.

Pen y Fan weather radar

Live radar maps

• Met Office (UK national weather service) provides a precipitation radar overlay for the Brecon Beacons area, updated every 15 minutes.
• Netweather (specialist weather site) offers a radar map with cloud cover and rain intensity layers.

How to interpret radar

• Green shows light precipitation, yellow moderate, and red heavy – useful for timing a departure before a band of rain arrives.
• Radar predicts short-term movement (1–3 hours), so combining it with the The Mountain Guide (mountain-focused forecast provider) hourly forecast gives you a powerful planning tool.

Precipitation alerts

• Both Met Office and BBC weather offer push alerts for heavy rain or thunderstorm warnings in the National Park.
• If radar shows deep red cells moving over the summit, consider postponing – Pen y Fan is exposed and lightning risk is real.

The pattern: Radar is your best short-term check, but always pair it with the mountain-specific hourly forecast for the summit.

Pen y Fan weather yesterday

Historical data from Met Office

• The Met Office (UK national weather service) archives observations for Pen Y Fan, including temperature, wind, and rainfall for each past day.
• Access the “Yesterday” tab on the Met Office location page or use their data download service for detailed hourly readings.

Weather stations near Pen y Fan

• Several automated stations operate within the Brecon Beacons – the nearest official station is at Sennybridge, providing reliable ground-level data.
• Station data helps you verify forecast accuracy: compare yesterday’s forecast high to the observed high to gauge model bias.

How to access yesterday’s data

• Met Office website: search “Pen Y Fan weather” and scroll to the “Observations” section.
• Mountain Forecast (specialist alpine forecaster) also shows recent actuals alongside its forecast for summit conditions.

The catch: Even with yesterday’s data, remember that mountain weather can deviate from station readings due to elevation differences.

Pen y Fan weather hourly

Hourly breakdown for today

• The Mountain Guide (mountain forecast specialist) provides an hourly forecast for Mynydd Pen-y-fan at 389 m, showing temperature, wind, and cloud cover every hour.
• For example, their 11:00 forecast shows partly cloudy at 20.4°C with SSE wind at 8 mph (13 km/h).

Wind and precipitation hour-by-hour

• Netweather (specialist UK weather site) breaks down wind speed and precipitation probability for each hour across the next 14 days.
• Wind gusts typically peak midday – a critical detail for hikes that traverse exposed ridges like the Corn Du approach.

Sunrise/sunset times

• Summer sunrise around 05:00, sunset around 21:30; winter sunset as early as 16:00.
• Factor these into your hourly plan – Pen y Fan is not a place to be caught in darkness.

What this means: Hourly windows give you the granularity to avoid the worst weather while maximising safe hiking time.

Pen y Fan weather december

Average December conditions

• December brings average highs around 5°C and lows near 0°C, with significant wind chill at the summit.
• Rainfall is frequent; snow covers the summit on roughly 5–7 days in the month (Snow-Forecast (mountain snow specialist)).

Snow likelihood

• Snowfall is possible at higher elevations (above 600 m) whenever temperatures dip below 0°C.
• Snow-Forecast (mountain snow specialist) provides a mid-mountain snow forecast specifically for Pen-y-Fan, tracking freezing levels.

Daylight hours

• Daylight shrinks to roughly 7–8 hours: sunrise after 08:00, sunset before 16:00. Plan to start your hike by 09:00 at the latest.
• Carry a headlamp even if you expect a short day – cloud cover can turn twilight to black by 15:30.

The implication: December hiking requires a tight schedule and thermal gear; daylight is your most constrained resource.

Pen y Fan weather mountain 2026

Seasonal outlooks

• Reliable forecasts beyond two weeks are not available. The Mountain Forecast (specialist alpine forecaster) and other providers only extend 14 days.
• General seasonal patterns: wetter in winter (October–March), milder in summer (June–August). Expect the same for 2026.

Climate trends

• Long-term data from the Met Office indicates that winter temperatures in the Brecon Beacons have risen about 0.5°C per decade since the 1980s.
• No specific 2026 forecast exists – use historical averages (e.g., December mean 2°C at summit) as a baseline.

Long-range forecasting limitations

• No legitimate source issues a “Pen y Fan weather 2026” prediction. Any site claiming such is either aggregating seasonal climate models or misrepresenting.
• The most reliable approach: check the 14-day Met Office forecast two weeks before your planned hike, then fine-tune with hourly data 48 hours out.

The catch: Without a crystal ball, the safest bet is to prepare for Pen y Fan’s default state – changeable and often harsh.

Pen y Fan weather timeline

• January – Coldest month; frequent frost and snow at summit (Snow-Forecast (mountain snow specialist)).
• March–April – Spring thaw; increasing daylight (Met Office (UK national weather service)).
• July–August – Warmest months; average high 18°C; popular hiking (Mountain Forecast (specialist alpine forecaster)).
• October–November – Autumn storms; high winds and heavy rain (Netweather (specialist UK weather site)).
• 2026 (projection) – Expected similar climate patterns; no long-range forecast available.

The pattern: The timeline shows a clear seasonal rhythm – plan your hike to match the weather window you can tolerate.

What’s clear and what’s not

The takeaway: Rely on the confirmed facts for your baseline preparation, and treat the uncertain elements as variables to monitor right before your hike.

Expert perspectives

“Today’s Pen y Fan forecast shows light rain totaling 3 mm, mostly falling Sunday night, with a maximum of 14°C on Friday afternoon.”

Mountain Forecast (specialist alpine forecaster)

“Mountain weather changes fast – always check the Met Office’s mountain forecast before setting out, not just the town-level outlook.”

Met Office Forecaster (UK national weather service)

For Pen y Fan hikers, the choice is clear: rely on summit-specific forecasts, not town-level data. Check the Met Office 14-day outlook for direction, then use Mountain Forecast or The Mountain Guide for elevation-corrected hourly data on the day. Carry extra layers always – conditions at 886 m are never the same as the car park.

Frequently asked questions