Cloud inversion forecast: Cairngorms

A cloud inversion traps fog in the valleys while summits sit in clear air and sunshine — the “sea of clouds” hillwalkers and photographers chase. Peakify analyses humidity, temperature profiles and cloud layers for every peak in the AI Mountain Explorer and scores the chance of an inversion. The mountains below currently have the best odds of putting you above the cloud.

Last analysed 18 Oct 2026. Best conditions are usually calm, clear nights after damp days — check each peak’s full forecast and sunrise time before an early start.

Best bet today · Sun 18 Oct
Ben Macdui North Top
1,294m · Cairngorms
94%
Excellent Best at 05:00 Sunrise 07:54 Low confidence

Good setup: warm air at summit height, wind at summit height, summit above the cloud. Be on top before 07:54.
Mountain Elevation Today Next 7 days
Ben Macdui North Top Cairngorms 1,294m 94% Excellent
Ben Macdui Cairngorms 1,309m 93% Excellent
Stob Coire Sputan Dearg Cairngorms 1,251m 92% Excellent
Cairn Lochan Cairngorms 1,214m 91% Excellent
Carn na Criche Cairngorms 1,265m 91% Excellent
Stob Coire an Lochain Cairngorms 1,235m 91% Excellent
Cairn Gorm Cairngorms 1,245m 89% Excellent
Beinn Bhrotain East Top Cairngorms 1,110m 88% Excellent
Beinn Bhrotain Cairngorms 1,157m 87% Excellent
Carn an t-Sagairt Beag Cairngorms 1,044m 87% Excellent
Cairn Toul Cairngorms 1,291m 86% Excellent
Carn Bhac SW Top Cairngorms 918m 86% Excellent
Sgurr an Lochan Uaine Cairngorms 983m 86% Excellent
Sron a' Cha-no Cairngorms 1,028m 86% Excellent
Stacan Dubha Cairngorms 1,014m 86% Excellent
Stob Coire Etchachan Cairngorms 1,082m 86% Excellent
The Devil's Point Cairngorms 1,007m 86% Excellent
Beinn a' Bhuird South Top Cairngorms 1,177m 85% Excellent
Ben Avon North Tor Cairngorms 1,138m 85% Excellent
Little Cairngorm Cairngorms 1,040m 85% Excellent
Stob Bac an Fhurain Cairngorms 1,076m 85% Excellent
Stob Coire an t-Saighdeir Cairngorms 1,213m 85% Excellent
Stob Coire an t-Sneachda Cairngorms 1,176m 85% Excellent
Braeriach Cairngorms 1,296m 84% Excellent
Carn Cloich-mhuilinn Cairngorms 942m 84% Excellent
Cnap Coire na Spreidhe Cairngorms 1,152m 84% Excellent
Creag an Leth-choin Cairngorms 1,053m 84% Excellent
Creag an Leth-choin North Top Cairngorms 1,026m 84% Excellent
Creagan a' Choire Etchachan Cairngorms 1,107m 84% Excellent
Fiacaill na Leth-choin Cairngorms 1,083m 84% Excellent
Stob an t-Sluichd Cairngorms 1,107m 84% Excellent
West Meur Gorm Craig Cairngorms 1,023m 84% Excellent
Carn an t-Sagairt Mor Cairngorms 1,047m 83% Excellent
Carn na Caim South Top Cairngorms 915m 83% Excellent
Cnap a' Chleirich Cairngorms 1,173m 83% Excellent
Creag an Dail Mhor Cairngorms 972m 83% Excellent
Fiacaill Coire an t-Sneachda Cairngorms 1,120m 83% Excellent
Monadh Mor Cairngorms 1,113m 83% Excellent
Beinn Mheadhoin SW Top Cairngorms 1,163m 82% Excellent
Carn a' Mhaim Cairngorms 1,037m 82% Excellent

Peaks in the Cairngorms

525 summits, the highest 200 shown. A dash means no inversion score in the last 36 hours: open the peak to run one. See all Cairngorms peaks.
Ben Macdui 1,309m Cairngorms 93% Excellent
Braeriach 1,296m Cairngorms 84% Excellent
Ben Macdui North Top 1,294m Cairngorms 94% Excellent
Cairn Toul 1,291m Cairngorms 86% Excellent
Carn na Criche 1,265m Cairngorms 91% Excellent
Sgor an Lochain Uaine 1,258m Cairngorms 74% Excellent
Stob Coire Sputan Dearg 1,251m Cairngorms 92% Excellent
Cairn Gorm 1,245m Cairngorms 89% Excellent
Stob Coire an Lochain 1,235m Cairngorms 91% Excellent
Cairn Lochan 1,214m Cairngorms 91% Excellent
Stob Coire an t-Saighdeir 1,213m Cairngorms 85% Excellent
Beinn a' Bhuird 1,196m Cairngorms 78% Excellent
Sron na Lairige 1,184m Cairngorms 75% Excellent
Beinn Mheadhoin 1,183m Cairngorms 81% Excellent
Beinn a' Bhuird South Top 1,179m Cairngorms 78% Excellent
Beinn a' Bhuird South Top 1,177m Cairngorms 85% Excellent
Stob Coire an t-Sneachda 1,176m Cairngorms 85% Excellent
Cnap a' Chleirich 1,173m Cairngorms 83% Excellent
Ben Avon - Leabaidh an Daimh Bhuidhe 1,172m Cairngorms 70% Excellent
Beinn Mheadhoin SW Top 1,163m Cairngorms 82% Excellent
Beinn Bhrotain 1,157m Cairngorms 87% Excellent
Derry Cairngorm 1,156m Cairngorms 80% Excellent
Lochnagar - Cac Carn Beag 1,156m Cairngorms 79% Excellent
A' Chioch 1,152m Cairngorms 71% Excellent
Cnap Coire na Spreidhe 1,152m Cairngorms 84% Excellent
Cac Carn Mor 1,151m Cairngorms 76% Excellent
Fiacaill a' Choire Chais 1,141m Cairngorms 82% Excellent
Ben Avon North Tor 1,138m Cairngorms 85% Excellent
Ben Avon West Top 1,138m Cairngorms 69% Good
Mullach Lochan nan Gabhar 1,124m Cairngorms 74% Excellent
Beinn a' Ghlo - Carn nan Gabhar 1,122m Cairngorms 81% Excellent
Clach Choutsaich 1,121m Cairngorms 68% Good
Carn Etchachan 1,120m Cairngorms 61% Good
Fiacaill Coire an t-Sneachda 1,120m Cairngorms 83% Excellent
Ben Avon South Tor 1,119m Cairngorms 80% Excellent
Stuc Gharbh Mhor 1,119m Cairngorms 65% Good
Sgor Gaoith 1,116m Cairngorms 77% Excellent
Sron Riach 1,114m Cairngorms 76% Excellent
Monadh Mor 1,113m Cairngorms 83% Excellent
Stuc Gharbh Mhor 1,112m Cairngorms 76% Excellent
Sgoran Dubh Mor 1,111m Cairngorms 71% Excellent
Beinn Bhrotain East Top 1,110m Cairngorms 88% Excellent
Carn a' Choire Bhoidheach 1,110m Cairngorms 79% Excellent
Creagan a' Choire Etchachan 1,107m Cairngorms 84% Excellent
Stob an t-Sluichd 1,107m Cairngorms 84% Excellent
Bynack More 1,090m Cairngorms 80% Excellent
Carn Eas 1,088m Cairngorms 82% Excellent
Beinn a' Chaorainn 1,083m Cairngorms 81% Excellent
Cuidhe Crom 1,083m Cairngorms 82% Excellent
Fiacaill na Leth-choin 1,083m Cairngorms 84% Excellent
Stob Coire Etchachan 1,082m Cairngorms 86% Excellent
Stob Bac an Fhurain 1,076m Cairngorms 85% Excellent
Beinn a' Ghlo - Braigh Coire Chruinn-bhalgain 1,070m Cairngorms 78% Excellent
Glas Maol 1,068m Cairngorms 77% Excellent
Creag a' Ghlas-uillt 1,067m Cairngorms 69% Good
Cairn of Claise 1,063m Cairngorms 80% Excellent
Airgiod Bheinn 1,062m Cairngorms 81% Excellent
Stob Dubh an Eas Bhig 1,061m Cairngorms 81% Excellent
Creag an Leth-choin 1,053m Cairngorms 84% Excellent
Carn Ban Mor 1,051m Cairngorms 79% Excellent
Glas Tulaichean 1,051m Cairngorms 78% Excellent
Eagles Rock 1,049m Cairngorms 64% Good
Carn an t-Sagairt Mor 1,047m Cairngorms 83% Excellent
Beinn Iutharn Mhor 1,045m Cairngorms 77% Excellent
Carn an t-Sagairt Beag 1,044m Cairngorms 87% Excellent
Little Cairngorm 1,040m Cairngorms 85% Excellent
Carn a' Mhaim 1,037m Cairngorms 82% Excellent
Carn an Righ 1,029m Cairngorms 77% Excellent
Sron a' Cha-no 1,028m Cairngorms 86% Excellent
Creag an Leth-choin North Top 1,026m Cairngorms 84% Excellent
West Meur Gorm Craig 1,023m Cairngorms 84% Excellent
Carn an Tuirc 1,019m Cairngorms 74% Excellent
Mullach Clach a' Bhlair 1,019m Cairngorms 73% Excellent
A' Choinneach 1,017m Cairngorms 77% Excellent
Beinn a' Chaorainn Bheag 1,016m Cairngorms 64% Good
Stacan Dubha 1,014m Cairngorms 86% Excellent
Cairn Bannoch 1,011m Cairngorms 66% Good
Beinn Udlamain 1,010m Cairngorms 65% Good
Beinn Dearg 1,009m Cairngorms 79% Excellent
An Sgarsoch 1,007m Cairngorms 77% Excellent
The Devil's Point 1,007m Cairngorms 86% Excellent
Fafernie 999m Cairngorms 66% Good
Broad Cairn 997m Cairngorms 76% Excellent
Meall Dubhag 997m Cairngorms 76% Excellent
Carn an Fhidhleir 994m Cairngorms 77% Excellent
Sgairneach Mhor 991m Cairngorms 65% Good
Cairn of Gowal 989m Cairngorms 69% Good
Creag Leacach 988m Cairngorms 75% Excellent
Mam nan Carn 986m Cairngorms 77% Excellent
Leth-chreag 985m Cairngorms 79% Excellent
Cairn of Gowal South Top 983m Cairngorms 62% Good
Creag an Dubh-loch 983m Cairngorms 69% Good
Sgurr an Lochan Uaine 983m Cairngorms 86% Excellent
Meikle Pap 980m Cairngorms 81% Excellent
Carn a' Gheoidh 976m Cairngorms 74% Excellent
Meall Buidhe 975m Cairngorms 62% Good
Diollaid Coire Eindart 974m Cairngorms 72% Excellent
A' Mharconaich 973m Cairngorms 67% Good
Meall Coire na Saobhaidhe 973m Cairngorms 75% Excellent
Creag an Dail Mhor 972m Cairngorms 83% Excellent
Little Glas Maol 972m Cairngorms 70% Excellent
Bruach nan Iomairean 970m Cairngorms 64% Good
Bynack Beg 970m Cairngorms 70% Excellent
Carn a' Chlamain 964m Cairngorms 75% Excellent
Druim Mor 962m Cairngorms 74% Excellent
Tolmount 958m Cairngorms 77% Excellent
Tom Buidhe 958m Cairngorms 61% Good
Creag Leachdach 957m Cairngorms 57% Good
Little Pap 956m Cairngorms 70% Excellent
Druim Sgarsoch 954m Cairngorms 75% Excellent
Beinn Iutharn Bheag 953m Cairngorms 75% Excellent
Mullach Clach a' Bhlair North Top 953m Cairngorms 71% Excellent
Carn a' Chlamain North Top 952m Cairngorms 70% Excellent
Meall Chuaich 951m Cairngorms 73% Excellent
Driesh 948m Cairngorms 67% Good
Carn nan Gabhar North Top 947m Cairngorms 79% Excellent
Carn Bhac 945m Cairngorms 74% Excellent
Creag Leacach SW Top 944m Cairngorms 75% Excellent
An Socach 943m Cairngorms 57% Good
Carn Cloich-mhuilinn 942m Cairngorms 84% Excellent
Carn na Caim 941m Cairngorms 76% Excellent
Big Brae 940m Cairngorms 68% Good
Mount Keen 939m Cairngorms 63% Good
An Socach East Top 937m Cairngorms 55% Good
A' Bhuidheanach Bheag 936m Cairngorms 72% Excellent
East Meur Gorm Craig 935m Cairngorms 68% Good
East Meur Gorm Craig South Top 933m Cairngorms 72% Excellent
The Cairnwell 933m Cairngorms 62% Good
Beinn Bhreac 930m Cairngorms 74% Excellent
Beinn Gharbh 930m Cairngorms 77% Excellent
Mayar 929m Cairngorms 63% Good
Beinn Bhreac West Top 928m Cairngorms 76% Excellent
Glas Mheall Mor 928m Cairngorms 72% Excellent
Craig of Gowal 927m Cairngorms 78% Excellent
Meall Odhar 922m Cairngorms 81% Excellent
Geal-charn 921m Cairngorms 59% Good
Carn nan Sac 920m Cairngorms 82% Excellent
Tom Dubh 920m Cairngorms 81% Excellent
Crow Craigies 919m Cairngorms 72% Excellent
Carn Bhac SW Top 918m Cairngorms 86% Excellent
Carn Bhinnein 918m Cairngorms 78% Excellent
Druim nam Bo 918m Cairngorms 80% Excellent
Carn Aosda 915m Cairngorms 77% Excellent
Carn na Caim South Top 915m Cairngorms 83% Excellent
Meall Gaineimh 914m Cairngorms —
Leathad an Taobhain 912m Cairngorms —
East Meur Gorm Craig North Top 910m Cairngorms —
Carn a' Bhutha 906m Cairngorms —
Carn an Fhidhleir South Top 906m Cairngorms —
Monega Hill 906m Cairngorms —
Finalty Hill 905m Cairngorms —
Aonach na Cloiche Moire 902m Cairngorms —
Meall Uaine 902m Cairngorms —
Beinn Mheadhonach 901m Cairngorms —
Leathad an Taobhain West Top 901m Cairngorms —
Culardoch 900m Cairngorms —
Meall Tionail 900m Cairngorms —
Beinn a' Chait 899m Cairngorms —
Bogha-cloiche 897m Cairngorms —
Meall a' Mhuirich 897m Cairngorms —
Creag Mhor 895m Cairngorms —
Carn Creagach 894m Cairngorms —
Cnapan Mor 893m Cairngorms —
Meall Odhar Mor 892m Cairngorms —
Carn Crom 891m Cairngorms —
Braid Cairn 888m Cairngorms —
Elrig 'ic an Toisich 887m Cairngorms —
Sgor Mor 887m Cairngorms —
Braigh nan Creagan Breac 885m Cairngorms —
Meall an Tionail 885m Cairngorms —
Glas Mheall Beag 882m Cairngorms —
A Bhuidheanach 881m Cairngorms —
Carn Greannach 880m Cairngorms —
Braigh Sron Ghorm 879m Cairngorms —
A' Chaoirnich 876m Cairngorms —
Bogha-cloiche West Top 876m Cairngorms —
Boustie Ley 876m Cairngorms —
Carn Mor 874m Cairngorms —
Braigh Clais Daimh 872m Cairngorms —
Crow Craigies South Top 872m Cairngorms —
Morven 872m Cairngorms —
Carn a' Chlarsaich 871m Cairngorms —
Clach Bhan 871m Cairngorms —
The Cairnwell North Top 871m Cairngorms —
Green Hill 868m Cairngorms —
Meall a' Choire Bhuidhe 868m Cairngorms —
Mullach Coire nan Dearcag 868m Cairngorms —
Craig Mellon 866m Cairngorms —
Carn Ait 865m Cairngorms —
Meall Odhar Loisgte 865m Cairngorms —
Carn Cruinn 863m Cairngorms —
Cathelle Houses 863m Cairngorms —
Conachcraig 863m Cairngorms —
Conlach Mhor 863m Cairngorms —
Creag an Dail Bheag 863m Cairngorms —
Cairn Lunkard 862m Cairngorms —
Carn Liath 862m Cairngorms —
Caisteal na Caillich 861m Cairngorms —
Creag Liath 861m Cairngorms —
Morrone 860m Cairngorms —

Cloud inversion forecast by area

Lake District Snowdonia Peak District Brecon Beacons Scottish Highlands Scotland Wales England All UK mountains

What is a cloud inversion?

Normally the air gets colder as you climb. In a temperature inversion a layer of warm air sits on top of cold, damp air in the valleys, so fog and low cloud are trapped below and the summits stand in sunshine above a sea of cloud. Inversions are most likely after a calm, clear night following a damp day, often in autumn and winter, and they usually burn off by late morning, so go early.

How a cloud inversion forms

ColderWarmer Height

After a damp day the wind has dropped and the sky has cleared. The air in the valleys still holds plenty of moisture.

What if…

A sea of cloud is likely: calm, clear and damp.

Read it step by step
  1. A calm, clear evening. After a damp day the wind has dropped and the sky has cleared. The air in the valleys still holds plenty of moisture.
  2. Heat escapes to the sky. With no cloud overhead to act as a blanket, the ground radiates its warmth straight out to space, and the air touching it starts to chill.
  3. Cold air drains downhill. Chilled air is denser than the air around it, so it slides down the slopes like water and gathers on the valley floor.
  4. The inversion forms. A pool of cold air now fills the valleys with milder air above it. Normally it gets colder as you climb; tonight it gets warmer. That flip is the temperature inversion.
  5. Mist over the water. Lakes and wet ground give the cold air the last bit of moisture it needs, so wisps of mist form there first. If you are going up, this is when to set off, by head torch.
  6. Fog fills the valleys. The trapped air keeps cooling until it reaches its dew point. Its moisture condenses into tiny droplets, and the cold pool turns to fog. Climbing through it, you see nothing but grey.
  7. A sea of cloud. The warm layer above works like a lid, so the fog cannot rise through it. Summits higher than the lid break out into clear air and sunshine.
  8. The best hour on top. Low sun lights the cloud tops gold and the hills cast long shadows across them. Turn your back to the sun: your own shadow may land on the cloud inside a rainbow ring, a Brocken spectre.
  9. The sun gets to work. Sunlight warms the slopes and the ground beneath the fog. Rising thermals stir the air and start to break the lid.
  10. The inversion lifts. The cloud rises, thins and breaks apart, usually by late morning. Then it is an ordinary day again, until the next calm, clear night.

Cloud inversion or fog?

From the valley floor an inversion just looks like fog. The difference is what is above it: if the summit is higher than the top of the fog layer, you climb out of the grey into clear air. The chances here are for standing above the cloud from each summit.

New to inversions? Read what a cloud inversion is and how to catch one, or get an alert on your phone when your hills look likely with the Peakify cloud inversion app.

Out after dark too? See the aurora forecast for the UK and the astronomy calendar.

Browse mountains by area

Lake District mountains Snowdonia / Eryri mountains Peak District hills Brecon Beacons mountains Cairngorm mountains Scottish Highlands mountains Yorkshire Dales hills Dartmoor tors Northumberland and Cheviot hills Galloway hills Isle of Skye mountains Isle of Arran hills Mourne Mountains Alps Munros and Scottish 3,000ft peaks The Wainwrights Corbetts Grahams Donalds Hewitts Nuttalls Marilyns Scottish mountains Welsh mountains English mountains Irish mountains

How the cloud inversion forecast for the Cairngorms works

What an inversion needs

Air gets colder as you climb. On a calm, clear night the ground loses heat, cold air drains into the valleys, and warmer air settles on top of it. If the valley air is damp enough, it condenses into fog, and the warm layer holds it down like a lid. Stand on a summit above that lid at dawn and you look across a flat sea of cloud.

How Peakify scores it

For each mountain, Peakify finds the lowest ground within 6 km of the summit, where fog would pool, and pulls an hourly forecast for the summit and that valley from Open-Meteo. It scores every hour from three hours before sunrise to two hours after and keeps the best.

Five ingredients build the score: a stable, layered atmosphere between about 750 m and 1,500 m, valley air close to saturation, dry air above the summit, overnight cooling in the valley, and a long night. Five checks then scale it: wind at summit height, overnight cloud, air pressure, wind in the valley, and the depth of the fog. Peakify estimates the fog top as the forecast boundary-layer height above the valley floor. Strong wind on the tops, or fog deeper than the summit is high, takes even a good setup close to zero.

How to read the table

The table ranks up to 40 peaks with a score from the last 36 hours, using today’s forecast. 70% and over is Excellent, 50 to 69% Good, and 30 to 49% Possible. Open a mountain for the full breakdown: the best hour, how long the inversion should last, which ingredients hold it back, a seven-day outlook and a confidence rating. Confidence is High when the ECMWF and Met Office models agree on a calm, clear valley at dawn, and Low when they disagree.

Limits

Read the percentage as a score of how well the ingredients line up. Forecast models work on grids 1 to 10 km across and can’t see into a narrow valley, so Peakify estimates the valley air from a coarser picture. Fog over a lake or in one side valley may not show. The table lists only peaks scored in the last 36 hours, so a quiet hill with a good setup can be missing until someone opens its page. And plan for the walk in: you’ll climb in the dark, through the fog, to reach the clear air.

Cloud inversion questions

Where in the Cairngorms has the best cloud inversion forecast today?

The table at the top of this page ranks summits in the Cairngorms by today's cloud inversion score, refreshed each morning from the latest forecast. Peaks that rise well above deep, sheltered valleys tend to score best, but the setup changes from day to day, so check again the evening before you go.

What is a cloud inversion?

A cloud inversion happens when a layer of warm air sits on top of cold, damp air in the valleys. Fog forms in the cold layer and can't rise through the warm one, so from a summit above it you look down on a flat sea of cloud.

When do cloud inversions happen in the UK?

Mostly in autumn and winter, on calm, clear nights under high pressure, often after a damp day. Long nights give the valleys more time to cool, and light winds let the cold air settle instead of mixing.

What time should I be on the summit?

Before sunrise. Peakify looks for the best hour between three hours before sunrise and two hours after, and each mountain page gives that time and the sunrise. Once the sun warms the valleys, the fog thins and lifts.

How high do I need to climb to see one?

Higher than the top of the fog. Peakify estimates the fog top from the forecast boundary-layer height above the lowest ground near the mountain and compares it with the summit. On a shallow fog morning a modest hill clears it. On a deep one, even a 900 m summit can stay in the murk.

How reliable is the cloud inversion forecast?

Use it as a guide and check again the evening before. Each mountain page shows a confidence rating: High when the ECMWF and Met Office models agree on whether the valley will be calm and clear at dawn, Low when they disagree.

Why isn't my mountain in the table?

The table ranks the 40 highest scores among peaks with a forecast from the last 36 hours. Peakify refreshes popular UK summits each morning and any other peak when someone opens its page, so open your mountain to score it.