A wild day on Cairn Gorm: summit wind broadly 35-50 mph, with gusts 60-70 mph around midday (storm-force winds).
Cairngorms 4000s weather forecast
Compare Cairn Gorm, Ben Macdui, Cairn Toul, Sgòr an Lochain Uaine and Braeriach in one forecast view.
Forecast comparison
Every summit is shown side by side. The combined grade gives extra weight to the weakest forecast.
A rough, clagged-in day on Ben Macdui: summit wind broadly 35-50 mph, with gusts 60-70 mph around midday (storm-force winds).
A wild day on Cairn Toul: summit wind broadly 35-50 mph, with gusts 60-70 mph around midday (storm-force winds).
A wild day on Sgòr an Lochain Uaine: summit wind broadly 35-50 mph, with gusts 60-70 mph around midday (storm-force winds).
A wild day on Braeriach: summit wind broadly 30-50 mph, with gusts 55-65 mph around midday (storm-force winds).
Weather data: Open-Meteo (CC BY 4.0). Adapted by Mountain Weather.
Planning the Cairngorms 4000s
The Cairngorms 4000s links five of Britain’s highest summits across a remote, exposed plateau and the Lairig Ghru. Even when the general pattern is settled, cloud, wind and temperature can differ across this large mountain area.
Use the challenge grade to compare dates, then inspect all five rows. The forecast does not account for river crossings, snow cover, navigation or the very substantial distance between summits.
Read Cairngorms 4000s route contextBest time of year for the Cairngorms 4000s
Balance the historical rain-and-wind pattern with daylight, snow and the demands of the route. This is seasonal context, not a forecast for your chosen date.
September, May and June lead the seasonal comparison
These months have the highest average share of settled rain-and-wind days across the challenge's represented areas within our May-to-September planning comparison. Small percentage differences are not a reliable reason to choose one week over another.
For the Cairngorms 4000s, daylight and remaining snow deserve particular attention. All five summits are above 1,200 m, and the long plateau crossings make a regional rain-and-wind percentage only one part of choosing a date.
Settled rain-and-wind days by month
Average of 1 regional sample, not the probability of a settled whole challengeGreen bars mark May to September. Percentages measure rain and gusts only, not sunshine, cloud-free summits, snow conditions or safety.
September
48% settled rain/wind in this area's strongest May-to-September month.
Sample: Cairn Gorm, 1,245 m.
Context for 5 challenge summits
Cairn Gorm, Ben Macdui, Cairn Toul, Sgòr an Lochain Uaine, Braeriach. Shared regional context does not imply identical summit conditions.
Based on our ERA5-derived regional mountain climate summaries, 1986 to 2025. Each distinct area counts once, so several peaks sharing a sample do not multiply its influence. These monthly summaries do not measure how often all summits were settled on the same day. Explore the mountain climate guide.
Weather data: Open-Meteo (CC BY 4.0). Adapted by Mountain Weather.