Why coastal weather asks more of your kit

A walk along the South West Coast Path or the clifftops of Pembrokeshire can serve up four seasons before lunch. Nowhere else in Britain does rain arrive so sideways, or with such enthusiasm. On the coast you are not dealing with a polite shower; you are dealing with salt-laden spray, gusts that push rain straight through a loosely woven jacket, and sudden squalls that appear from behind a headland with no warning at all.

That combination changes what you need from waterproof clothing. Inland, a decent shell can be a bit of a compromise. On an exposed coastal path, it has to cope with wind pressure driving moisture through seams, with humidity rising as you climb, and with the fact that you will probably be wearing it for hours rather than minutes. Choose well and a blustery walk stays enjoyable. Choose badly and you will be damp, chilled and miserable within the first mile.

Breathability matters as much as waterproofing

It is tempting to fixate on the waterproof rating, but the two numbers work together. A jacket that keeps the rain out and traps your sweat in will leave you just as wet, only from the inside. Look for a hydrostatic head of at least 10,000mm for general coastal walking, and 20,000mm if you plan to be out on exposed headlands in proper weather.

• Hydrostatic head tells you how much water pressure the fabric resists before it leaks. Higher is better, but there is a point of diminishing returns.
• Breathability is usually expressed as a RET or MVTR figure. Lower RET is better; a RET under 6 is genuinely breathable.
• Pit zips are worth their weight in gold. Being able to dump heat on a steep climb without removing your shell is the single most useful feature on a coastal jacket.
• Ventilated pockets that double as core vents help on milder, drizzly days when the wind is behind you.

Be honest about how you walk. If you plod gently and stop often, you can accept slightly lower breathability. If you stride uphill with a rucksack, prioritise it.

The hood is where cheap jackets betray you

On the coast, the hood does most of the work. A thin, flappy hood that collapses in the wind is worse than useless, because it funnels rain down your neck. What you want is a hood with a stiffened or wired peak, so it holds its shape and keeps rain off your glasses, and at least two points of adjustment — one at the back to pull it in, and cords at the sides to cinch it around your face.

Check the collar height too. A high collar that sits above the chin, ideally with a soft brushed lining, keeps drips from running down your front. When you try a jacket on, put the hood up over a hat and turn your head from side to side. If the peak swings across your eyes or the hood pulls the whole jacket up, keep looking.

Cut, cuffs and hem: keeping the weather out

Fit is a practical matter on the coast, not a style one. You need enough room underneath for a fleece or light insulated midlayer, but not so much that the fabric billows and flaps.

• Sleeves should reach the base of your thumb when your arms are stretched forward, as they will be with walking poles.
• Cuffs need adjustable hook-and-loop tabs, not elastic, so you can seal them over gloves.
• Hems should be adjustable with a drawcord, and slightly dropped at the back to cover your seat when you bend or sit on a stile.
• Zips should have a storm flap behind them, and ideally be water-resistant rather than fully waterproof — the latter are stiffer and harder to use with cold hands.

Packability, layering and what else goes in the bag

Most coastal walks are day walks, so your waterproof can live in your rucksack until needed. A shell that folds into its own pocket and weighs under 400g is a joy; a heavy, stiff jacket will stay in the bag and you will get soaked in the one shower you did not expect. Look for taped seams, which should be sealed on the inside of every stitch line.

Pair your jacket with waterproof overtrousers that have full-length side zips. Being able to pull them on over boots without sitting down is a small thing that feels enormous in a gale. Add a dry bag for your phone and spare layers, a warm hat that fits under the hood, and thin waterproof gloves. These accessories often make more difference to your comfort than the jacket itself.

Reading the label, then keeping it working

Before you buy, check for fully taped seams, a durable water repellent finish, and a fabric that suits your budget without pretending to be something it is not. A mid-range jacket with excellent hood design and pit zips will out-perform a stiffer, more expensive one that does not fit you properly.

Once it is yours, look after it. Mud and salt clog the fabric and stop it breathing. Wash it gently with a technical cleaner rather than detergent, then either tumble it on a low heat or warm it briefly with an iron through a cloth to reactivate the water repellent finish. When water stops beading and starts soaking in, reproof it. A well-cared-for jacket will keep you dry on blustery clifftop walks for years, which is exactly what coastal Britain demands of it.