Argyll and Loch Lomond mountain weather forecast.

The Arrochar Alps, Crianlarich and Argyll hills. Height-aware guidance for wind, cloud, rain and temperature.

Mountain Weather brief

Argyll and Loch Lomond

Saturday 17 October 2026 · The Arrochar Alps, Crianlarich and Argyll hills

Confidence: Unavailable Why?

Uncertainty over sky cloud cover and sunshine.

What matters most

A good day in Argyll and Loch Lomond: dry, with light winds and clear tops for most of the day.

High-ground wind · 900 m10-20 mph northwesterly Gusts · 900 m15-25 mph Cloud base1300-1700 m Feels like · 900 m-4 to 0°C
Regional median

Sunshine and sky

Less sunshine later. Sunshine is indicated less often later in the day.

Modelled sunshine9.8 h88% of daylight
Early2 h sunshine
Midday4 h sunshine
Later1.8 h sunshine

These are direct modelled sunshine hours during daylight, not the probability of sunshine. Cloud cover and summit cloud are assessed separately in the forecast above. The regional median prevents one unusually bright or dull summit cell defining the whole area.

Overnight forecast: 17:00–08:00 (UK local time), in Wild camping below.

Morning · 08:00–12:00GoodSummit winds around 10-20 mph. Gusts around 15-25 mph are possible on exposed ground. Summit cloud is more persistent early in this period, with better prospects later.
71
Afternoon · 12:00–17:00ExcellentSummit winds around 5-15 mph. Gusts around 10-20 mph are possible on exposed ground. Summit cloud is more persistent early in this period, with better prospects later.
90

Conservative regional grades across representative summits, so one sheltered hill does not overstate the wider area.

01

High-ground wind (900 m)

At around 900 m, expect a north-westerly wind of 10–20 mph, gusting 15–25 mph.

02

Walking impact

Noticeable on exposed ground, but unlikely to impede most walking.

03

Ground conditions

The ground is likely to be wet after recent rain.

04

Rain and showers

It should stay dry.

05

Cloud-free summits

Clear-summit estimate: about 90% early, about 65% around midday and about 90% later.

06

Cloud and visibility

Cloud on the tops early should lift off them by mid-morning. The cloud base could be as low as 700–1000 m around midday. Mist or fog is possible in some valleys early on. It will look largely cloudy overhead, but that cloud should mostly stay above the tops. The air should be clear, so expect far-reaching views as long as the tops stay clear.

07

Temperature and wind chill

At around 900 m it will be 0 to 4°C, feeling like -4 to 0°C in the wind. It turns milder through the day. Take a hat, gloves, a windproof and a spare warm layer.

08

Freezing level

The freezing level is around 1000–1300 m, so it will be below freezing on the tops.

09

Daylight

Sunrise 07:54, Sunset 18:13, about 10.3 hours daylight.

Overnight · 17:00–08:00Wild campingBetaAcross these hills, a mixed night to camp, mainly because of the cold: dry, with light winds. 59Mixed · 600 m View detailsHide details
Regional night beginning Saturday 17 October 2026

Full regional overnight outlook

Across these hills, a mixed night to camp, mainly because of the cold. Light winds on open ground, gusting no more than about 15 mph. It should stay dry. Overnight lows of about 3°C at 900 m.

Overnight rain0.0 mmOpen ground · 600 m6 mph · gusts 12 mphMorning pack-upNo wet signal

Moon overnight

Waxing crescent moon

Illuminated disc
44%
Moonrise
Outside this window
Moonset
21:32 BST

Cloud and terrain vary across the area. Illumination describes the sunlit part of the Moon, not brightness at your pitch.

Overnight window: 17 Oct, 17:00 BST to 18 Oct, 08:00 BST. Approximate open-horizon times; hills can hide the Moon. Still take a headtorch.

Representative location: 56.386, -4.540. Times vary across the area.

300 m59 · mixed
Wind / gust
5 mph / 10 mph
Coldest
4.0°C
In cloud
0% of modelled night
Condensation
Low
600 m59 · mixed
Wind / gust
6 mph / 12 mph
Coldest
4.0°C
In cloud
0% of modelled night
Condensation
Low
900 m59 · mixed
Wind / gust
7 mph / 14 mph
Coldest
3.2°C
In cloud
0% of modelled night
Condensation
Low

Open-hillside guidance across representative hills. Local shelter, ridges, tent design and the exact pitch can change conditions substantially. Read about sleeping-bag comfort ratings, pitching in strong winds or using the wild-camping forecast.

Daytime · exposed rockClimbing & scramblingBetaSub-zero temperatures and moisture may leave icy patches on exposed rock. Rock may be damp or still drying. 23Poor · Poor View detailsHide details
Regional rock conditions · sampled mountain terrain

Regional climbing & scrambling outlook

A broad guide to dampness and exposed rock across the area, not a forecast for every crag. Lower, sheltered crags and individual rock types may behave differently.

Conditions for exposed scrambling across the area look poor (23/100). Some rock may remain damp or incompletely dried, especially in shade and seepage lines. Mapped summit-point geology across the representative hills includes psammite, pelite or semipelite, volcanic rock and granite, gneiss or gabbro. Rock can therefore respond differently to moisture between crags and routes.

Rock surfaceDry overhead; seepage uncertainExposed gust19 mphRain0.0 mm
Mapped rock across sampled summits3 broad familiesSummit samples, not a survey of every crag
psammite, pelite or semipelite 62% 5 representative summitsDry quartz-rich bands can be grippy, while mica-rich or foliated sections, lichen and vegetation may become slippery when wet.volcanic rock 25% 2 representative summitsOften grippy when dry, but volcanic rocks vary widely; wet lichen, smooth holds and local seepage can still make them slippery.granite, gneiss or gabbro 12% 1 representative summitGenerally grippy when dry and often still positive when damp, but wet slabs, lichen, polish and drainage lines can remain slippery.

Representative summit-point samples across the region; individual crags and routes may differ.

Generic exposed hands-on-rock terrain across representative summits; mapped summit-point geology is a broad regional sample, not a named-route survey. Contains British Geological Survey materials © UKRI 2026. How to use the climbing and scrambling forecast.

Recommended kit for this dayWeather-aware packing prompts, plus your core hillwalking kitView kit

For a day hillwalk, not a complete route-specific checklist. Carry navigation and backup you can use, warm and waterproof layers, suitable footwear, food and water, a headtorch, emergency shelter, first aid and a way to call for help. Snow, ice, technical terrain and overnight trips need additional equipment and skills.

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Weather data: Open-Meteo (CC BY 4.0). Adapted by Mountain Weather.

Updated 12 October 2026 at 15:29 UTC. See typical weekly and monthly conditions for Argyll and Loch Lomond.

More context for your hill day

Check the approach as well as the tops

Compare midge conditions by day and height, or look for a possible cloud inversion. For Snowdon and Tryfan, camera-derived cloud-base observations add a view of conditions already seen on the slopes.