Black Diamond Coefficient Storm Hoody | Tested and reviewed

The new Black Diamond Coefficient Storm is an update to its alpine climbing focused Coefficient Hoody, and one that should bring it to the attention of hikers and hillwalkers.

from Black Diamond
RRP  £118.25
Man wearing Black Diamond Storm Coefficient fleece jacket on a mountainside with LFTO star ratings

by Ben Weeks |
Updated on

This is not the first time we’ve expressed a fondness for the traditional fleece. In fact, it’s a fairly regular occurrence because they're just such a versatile type of hiking jacket.

Perhaps it’s because, on the great ever-spinning wheel of trends and fashions, it’s fleece’s time to come back around again. Or maybe, and this is the explanation we’re most inclined to follow, fleeces are simply getting better and bear increasingly little resemblance to the fleeces we regard as ‘traditional’.

Black Diamond’s Coefficient Hoody is a case in point; a highly technical lightweight mid layer that allows alpinists to move efficiently over some of the most challenging mountain terrains. This makes sense. In the same way that high-performance cars tend to be the first invested with new technology, it’s outdoor gear that gets used in the most adventurous pursuits that sees the earliest improvements. Often these developments filter down into more general equipment, but sometimes they occur in kit that sits across the boundary between performance and more typical use.

Price: £123.45 (RRP £130)


  • Highly breathable
  • Reasonably weather resistant
  • Athletic and unrestrictive
  • A great layering piece


  • Relatively pricey for a fleece
  • Not as warm as thicker fleeces
  • Not as windproof as a softshell

Which brings us neatly onto the new Black Diamond Coefficient Storm Hoody. Like its Storm-less stablemate, it was developed for alpinists. But the features that set it aside from the regular Coefficient also make it an ideal mid layer for hikers on less vertical terrain. Chief amongst those is its improved weather resistance and packability, but there are plenty of others that will be as appreciated by walkers as they are by climbers. So, let’s take a closer look and see what the new Black Diamond Coefficient Storm Hoody has to offer.

Weather resistance

Closeup of water beading on Black Diamond Coefficient Storm Hoody fabric

In addition to being more windproof than a typical fleece, the tightly woven outer face fabric has been given a DWR (durable water repellent) treatment, making it moderately weather resistant. It’s by no means waterproof – you’ll still need to pack a hard shell – but the Coefficient Storm Hoody’s ability to shrug off a little light drizzle means your hard shell might be able to stay in your pack a little longer.

The DWR is PFC-free and the material itself is Bluesign approved.

Snug but stretchy

Black Diamond Coefficient Storm Hoody sleeves

The fit of the jacket is quite snug – there’s not a huge amount of space underneath for extra layers. This snug fit means it’s easy to wear the Coefficient Storm Hoody under other layers, be that another insulating layer in cold conditions, or directly under a shell if it’s particularly wet. The stretch in the fabric from the elastane means it’s in no way restrictive, allowing plenty of movement when hiking or scrambling.

Surprising warmth

For its light weight and slim build, the Coefficient Storm offers an impressive level of heat retention. It achieves this through the use of a ‘grid back’ – a pattern of fleecy squares that help trap warmth separated by channels that permit excellent breathability.

LFTO tester putting phone into Black Diamond Coefficient Storm Hoody chest pocket

Perfectly pitched pockets

You don’t want to be weighing a fleece down by stuffing its pockets full of stuff. But there is almost the perfect arrangement of pockets on the Coefficient Storm: two handwarming pockets on the waist (for keeping fingers warm when loitering) and a single chest pocket that is ideal for a phone (even a large-screen model), wallet or compass.

Black Diamond Coefficient Storm Hoody fleece hood

Light and nimble

Whether for alpinism or UK hiking, the Coefficient Storm Hoody has been designed to be lightweight and relatively minimal. Aside from the pockets, features are slim. The hood, cuffs and hem are elasticated, but not adjustable – there are no drawcords or cinch tabs. The result is that the men’s medium weighs 359g and can be stowed in its own pocket.

Price and competition

£130 is either very expensive or remarkable value, depending on your previous experiences of fleeces. If you're used to paying the bargain prices for the most basic of fleeces - the sort found in garden centres or discount outdoor retailers - then £130 is probably almost three times what you're used to paying.

But, to be fair, the Black Diamond Coefficient Storm Hoody is a technical fleece with loads of great design features, and viewed through that lens it's a very fair price indeed. Sure, it's more expensive than the Montane Fury Lite, but it's very similarly priced to the The North Face Summit Series Futurefleece, cheaper than the Mountain Equipment Shroud, and an absolute bargain compared to the ThruDark Centurion Alpine. And, in my opinion, it's as good as any of these, and better than most.


All in all, the Black Diamond Coefficient Storm Hoody is a versatile piece of outdoor apparel that, while still just about a fleece by definition, outperforms most other mid layers in that category thanks to its modern yet minimalist design.

How we tested the Black Diamond Coefficient Storm Hoody

LFTO and Trail Magazine Gear Editor Ben Weeks put the Black Diamond Coefficient Storm Hoody to work during several days hiking and camping in the Lake District and North Wales (Trail magazine's Tom Bailey appears in the photos).

Ben has been with Trail for over 10 years, and is a qualified Mountain Leader and Climbing Instructor. He loves thrilling scrambles and gnarly Scottish winter routes so is a master at putting technical gear and cold weather kit through its paces.

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