North-West Highlands Midges in May — Risk, Peak Times, Kit
Noticeable at dawn and dusk. Repellent recommended. Torridon to Assynt — heavily forested glens, low pressure on exposed coast and ridges, brutal in sheltered hollows. The combination of latitude and Atlantic humidity gives the densest swarms outside Lochaber proper.
Current risk
North-West Highlands in May: Moderate. Noticeable at dawn and dusk. Repellent recommended.
When they bite
Peak biting windows are dawn 6–8am and dusk 5–7pm. Average highs into the mid-teens on the coast by late May; sheltered glen floors warmer still. First proper midge hatch typically in the second half of the month — Wester Ross and Torridon valley floors first, Assynt and inland Fisherfield a week or two behind.
What to wear
- Smidge repellent (75ml)
- Light-coloured long-sleeve baselayer — midges have a strong preference for dark clothing.
Tactical notes
May is the transition month in the North-West Highlands. The first three weeks are typically still cold enough on the coast and inland for midge pressure to stay low or negligible. The last week often delivers the first proper hatch of the year — driven by a warm settled spell, calm humid evenings, and ground temperatures finally pushing above the emergence threshold in the sheltered low-lying spots.
The pattern is geographic. Coastal Wester Ross — the strath at Kinlochewe, the lower [Glen Torridon](/glens/glen-torridon) car parks, the boggy ground around Slattadale and Loch Maree — sees the first significant emergence. Inland Fisherfield and the Assynt interior typically lag by a week to ten days because of altitude and longer-lying snow in the higher corries. By the end of May, almost every glen floor below 400m is potentially active in calm warm weather; ridges, exposed coast and anywhere with consistent wind remain genuinely midge-free.
May is therefore the last month to plan a North-West Highlands trip without making midges a primary kit consideration. The [Beinn Dearg](/hillwalking/munros/beinn-dearg-north-west-highlands) round above Ullapool, the [Beinn Alligin](/hillwalking/munros/beinn-alligin-sgurr-mor) traverse in Torridon, the [Cape Wrath Trail](/long-distance/cape-wrath-trail) finish for cold-spring walkers — all still very doable without head net misery. Carry a 75ml Smidge for the calmer late-month evenings and accept that the first dawn-and-dusk windows in [Carnmore bothy](/bothies/carnmore) or by Loch Stack might cost you a bit of bare-skin discipline. The wild swimming windows at [Corrieshalloch Gorge](/wild-swimming/corrieshalloch-gorge-pool) and [Achmelvich Beach](/wild-swimming/achmelvich-beach) stay open all month — coastal sea breeze almost always wins over Atlantic-edge midge pressure.