Mountain forecast guide

Mountains can be inhospitable and dangerous places for the ill prepared. From one hour to the next, from one hill to the next, they can exhibit a dramatic variation in weather conditions. Whether it's a well-planned expedition or a spur of the moment decision to go to the hills, it is important to check the forecast.

We provide mountain forecasts for a selection of the main mountain areas and those which have the highest visitor figures. Forecasts are issued twice per day and cover daylight hours. This content is designed for walkers, mountaineers and others taking part in outdoor activities in mountainous areas.

Mountain forecasts on our website

All mountain forecast information is gathered together on the Mountain forecast page. The map highlights the areas for which mountain forecasts are available. Each region is coloured depending on the highest hazard risk for that area. More about hazards and colours

mountain risks

Mountain Forecast

Choose one of the regions on the map to display the following further information agbout your chosen location:

print icon Clicking on the print icon will give you a print out of the warnings and hazards for your chosen area along with the weather overview information.

Warnings and weather hazards

This section shows you the severe weather warnings in force for your chosen region along with a summary of the hazards with colours showing the level of risk of the hazard occuring.

Warnings and weather hazards

These mountain weather hazards apply at or above 1000ft, reflecting the more severe conditions which can occur at altitude. You will see that there are more types of mountain weather hazrd than severe weather warning type, again reflectiong the different types of severe weather which can commonly occur at height. There will be occasions when mountain weather hazards are in force for your chosen mountain forecast area but there are no severe weather warnings in force for the same area. It is unlikely that there will be occasions when a severe weather warning will be in force but a comparable mountain weather hazard is not.

Weather overview

This section displays the more details forecast content for your chosen area, including summit level winds and temperatures.

Mountain Weather overview

Click on the days along the top to view the forecast for the next few days. A detailed forecast is available for the following day with a brief outlook available beyond that.

You can also swap to the weather overview for another region by using the drop down navigation tab above the forecast.

Location map

The location map allows you to access the 5 day forecasts for specific summits or places of interest within your chosen mountain forecast region.

Location map

 To access he five day forecast for one of the summits or places of interest click on the marker Location marker

Learn about our Mountain Area Forecasts

The content in this section is designed specially to meet the requirements of walkers, mountaineers and others taking part in outdoor activities in mountainous areas and was designed using their input. The mountain forecasts are designed to be easy to use and understand, however, the following information may help you to interpret the forecasts.

Availability

We provide mountain forecasts for a selection of the main mountain areas and those which have the highest visitor figures.:

  • Scottish West Highlands
    Covering the areas of Trossachs, Argyll, Lochaber, the north-west Highlands and Skye.
  • Scottish East Highlands
    Covering the areas of the Grampian Mountains east of Rannoch Moor and including the Cairngorms.
  • Lake District National Park
  • Yorkshire Dales National Park
  • Peak District National Park
  • Snowdonia National Park
  • Brecon Beacons National Park

Hazard criteria

The mountain forecast hazard section covers a range of hazards likely to affect those outdoors in mountainous areas. The colour for each hazard is determined by the level of risk of it occurring.

mountain risks

The following tables details these hazards along with criteria for issue and the likely impacts you may experience.

Criteria and Impact for Hazards

Hazard

Criteria

Impact

Blizzards

Moderate or heavy falling snow (either continuous or in the form of frequent showers) with winds speeds of 30 mph or more and a reasonably extensive snow cover.

Near zero visibility and total disorientation likely.

Heavy snow

Heavy snow falling during the day with over 15 cm (6 inches) of average depth of fresh snow expected.

Significantly reduced visibility, potential danger with losing footing if paths are obscured. Navigation more difficult. Progress likely to be affected to a considerable degree. Marked increased risk of white-out conditions. Marked increased risk of hypothermia if snow is wet

Storm force winds

Winds with consistent gusts above 70 mph.

Risk of losing one's footing in gusts. Danger increased on exposed ridges. NB: When gusts of over 90 mph expected, winds will be 'Hurricane force' with likelihood of being blown over.

Gales

Winds with consistent gusts above 50 mph.

Considerable buffeting.

Persistent and extensive hill fog

Cloud bases at or below 600 metres (500 metres for Peak District) for two hours or more.

Please note that on some high level plateaux, especially the Cairngorms, as well as on Ben Nevis, considerably higher cloud bases can be as hazardous.

Significantly reduced visibility resulting in major navigation difficulties, especially where there is extensive snow cover with the risk of white-out conditions. White-out conditions are defined as when one's field of view becomes totally featureless due to a combination of mist or fog and deep snow cover, with or without falling snow.

Thunderstorms

Lightning strikes.

Lightning strikes are likely to cause danger, especially on exposed tops and ridges

Severe chill effect

When cooling is greatly increased by strong winds, normally exceeding 35 mph. mean wind speed. If driving rain or sleet is also forecast winds may be lower than 35 mph.   

Please note that other factors such as mist, sunshine, precipitation and snow cover will either mitigate or enhance cooling.

Considerable risk of hypothermia and frostbite, unless adequately equipped and protected. NB: Even though winds in valleys or glens may be light, sudden and very marked increases can occur at higher levels.

Heavy persistent rain

Persistent, heavy, rain (or sleet), lasting at least 3 hours, or over 40 mm expected in 24 hours, starting from dusk of the previous day.

Risk of major discomfort unless adequately equipped and protected. Reduced visibility possible. Watercourses likely to become rapidly in spate and marked increased risk of very boggy terrain. Marked increased risk of hypothermia, especially if combined with strong winds, unless adequately protected.

Strong Sunlight

Exposure to moderate or high levels of UV

During snow conditions, significant glare off the snow pack.

Please note: The Strong Sunlight hazard used in the Mountain Area Forecasts is based on both the UV level corrected for altitude and weather conditions in each mountain area. In winter, where there is extensive snow cover and strong sunlight, this also takes into account the risk of glare off the snow pack. For this reason, the UV index on the Mountain Area Forecasts may differ from those on our standard forecasts.

Risk of sunburn - seek shade during midday hours, cover up and wear high protection factor sun screen.

High levels of reflected light which may be unpleasant and potentially lead to snow blindness - wear appropriate eye protection.

Guide to forecast content

The table below highlights the different sections of the mountain forecast and provides additional supporting information.

Key to the components within the Mountain forecast

Weather Element

Description

Overview

A brief summary of conditions over the area in question (including all the Scottish Highlands for the Scottish areas, and all of Wales for the Welsh areas). As suggested, this is a summary and should be used in conjunction with the other parts of the Mountain forecast in order to understand the expected weather.

Hazards

The level of risk of several hazards is provided. This is assessed as either Nil, Low, Medium or High and shown using a traffic light system. Where a risk is identified, additional information is provided. These are described for Day 1 of the forecast only.

For detail on the criteria and impacts of the various hazards see the mountain hazards key.

Weather Summary and Probability of Precipitation

A weather symbol is provided to give a summary of the weather conditions for each three hour period. This gives an indication ofthe most likely conditions across the majority of the area. You should remember that this symbol will not be representative of the conditions at every location in the area and at all times through the period. This should be used in conjunction with the other parts of the Mountain forecast in order to understand the expected weather.

The Probability of Precipitation section indicates the percentage likelihood of precipitation falling in the area during the period. This could be in the form of rain, drizzle, sleet, snow etc. More detail will be contained in the detailed forecast section.

Weather

The forecasts are for all levels, but will emphasise weather above 600 metres for the Scottish areas, 500 metres for the Lake District and Snowdonia, and 400 metres for the Peak District, Yorkshire Dales and Brecon Beacons. Please note that if precipitation, especially heavy snow, is forecast, the visibility will be markedly reduced.

Visibility

Also known as Clarity of Air, this can be classified in the following ways:

i. Very Hazy - less than 10 km

ii. Hazy - less than 30 km

iii. Good - between 30 and 60 km

iv. Excellent - over 60 km

Hill fog

Indicates whether low cloud will cover the ground within a region and is classified in the following ways:

i. Persistent - covering ground over 90% of the time

ii. Periods - between 50 and 90% of the time

iii. Occasional - between 20 and 50% of the time

iv. Occasional Patches - less than 20% of the time

Maximum winds

Winds speeds cited are the highest expected, these normally occurring on exposed peaks or ridges, though it should be noted that winds in mountains are very turbulent. Any changes during the course of the day will be emphasised, as will any differences in speeds over the forecast area.

Temperatures and Freezing Level

Freezing Level is defined as the level above which snow is expected to settle, or the level above which the ground is expected to be frozen. Account is not taken of melting of surfaces in direct sunshine during the day. In most situations, except in mid-winter, this is to be expected during the middle part of the day. In late spring or early summer it is common to find the snow cover frozen, even when other surfaces are not. Please note that the freezing level may not appear to tie in with the temperature at 900 metres.

Warnings

When severe weather warnings have been issued for the area this will be indicated at the bottom of the forecast.

Outlook

A brief text summary for days three to five.

Ground Conditions

Currently ground conditions are only available for a limited number of areas where we are able to guarantee reliable information from authoritative partners. This information is generally only available during the winter season, but may be available at other times of year during severe weather:

Lake District - October to April
Snowdonia - October to April

Additional information

The mountains can be a dangerous place throughout the year. The Met Office, in conjunction with the Welsh Assembly Government, British Mountaineering Council, Mountain Leader Training and Sports Wales, have produced a series of short videos on the skills you will need throughout the year and how to stay safe on the mountains.

You can also access our mountain forecasts while you are out and about via your mobile phone.

Last updated: 1 April 2014