Yr Eifl weather tomorrow, this weekend and 14-day summit forecast
561 m · Anglesey and the Lleyn Peninsula · OS grid SH364447
Yr Eifl is the highest hill on the Llyn Peninsula, rising from the sea above Nant Gwrtheyrn, with the Iron Age hillfort of Tre'r Ceiri on its eastern top.
There is no recent summit forecast cached for Yr Eifl right now. The main Yr Eifl page loads the live forecast when you open it.
Yr Eifl weather today, tomorrow and this weekend
There is no recent summit forecast cached for Yr Eifl right now. The main Yr Eifl page loads the live forecast when you open it. Open the live Yr Eifl forecast.
Yr Eifl 14-day summit weather forecast
The 14-day table appears here once a recent summit forecast is cached for Yr Eifl. Until then, the main Yr Eifl page shows the live 14-day forecast.
How the Yr Eifl summit forecast is made
The numbers come from the Open-Meteo weather model for the summit's position at 561 m, in the mountain's local time. A valley forecast would understate the summit badly, so the wind is worked out at summit height from the model's upper-air winds: the standard 10 m wind sits over the model's smoothed ground and is roughly half what an exposed top gets.
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. The verdict is the same one shown on the main peak page and in the Peakify app.
"Feels like" is the coldest apparent temperature of the day, which combines air temperature, wind and humidity. On a windy summit it can be well below the air temperature, so pack for that figure, not the high.
For a second opinion before a big day, read the Met Office mountain forecast or MWIS for the area. They are written by forecasters and cover hazards such as cloud on the tops and visibility that a model table can't.
Questions about Yr Eifl
What is the Yr Eifl weather tomorrow?
There is no recent summit forecast cached for Yr Eifl right now. The main Yr Eifl page loads the live forecast when you open it.
Is there a 14-day Yr Eifl weather forecast?
Yes. This page lists up to 14 days of summit weather for Yr Eifl, each with a Good, Marginal or Poor verdict. Days 8 to 14 are less certain: use them to spot a settled or stormy spell, not to plan a day.
Where does the Yr Eifl summit forecast come from?
From the Open-Meteo weather model for the summit's position at 561 m, refreshed every few hours. Wind is worked out at summit height from the model's upper-air winds, because the standard 10 m wind is roughly half what a summit gets.