Best waterproof running jackets for men and women
The best waterproof running jackets can bring much-needed comfort and protection on runs in foul weather. Here, 220 Triathlon's gear experts test, rate and review 16 options for men and women

While a bit of rain on a short run isn’t really any trouble, if you’re running further, or it’s both cold and wet, then the best waterproof running jackets can be a saving grace.
But which jacket should you pick? To help you make that decision, we’ve tested a total of 16 running jackets split between both men and women.
But before we get to the reviews, let’s talk about what we tend to look for…
What should I look for in a waterproof running jacket?
The first question must focus on how the jacket will be used and what your specific needs are.
If you run hot while exercising, you’re not going to want anything too stuffy, but rather something with decent breathability and ventilation.
You can easily layer up with warmer base layers underneath, too, so you don’t need to worry about getting any warmth from your waterproof running jacket. That way, you can add or remove layers as you get cold or hot.
So what should you look for when choosing a waterproof running jacket? Well, first and foremost, it needs to keep the weather out. Read more about that in the next section of this article.
Given the nature of running, a good jacket will also be breathable or allow you to ventilate and regulate your temperature. To that end, vents, mesh-lined pockets and breathable fabrics can be a godsend.
Hoods are down to personal preference, but if the jacket has one we like it to fit close to the head so it doesn’t blow around. If you can roll it down and fasten it away, even better.
We also like to see elasticated cuffs, a close-fitting hem (often aided by adjustment points), hi-vis detailing and a pocket for essentials (though this is less important if you use a pack/belt while running).
That aside, it also has to fit well so it doesn’t catch the wind, otherwise it can feel like a parachute on really breezy runs.
Weight and pack size is key so you can stow your jacket away if it stops raining or you overheat, while we also like it to look good – obviously!
Of course, you may just want something super lightweight to chuck in a pack as mandatory kit at a race – just make sure you check the requirements for your race first, as some races will stipulate taped seams and a minimum hydrostatic head rating.
Tried and tested: best waterproof running jacket at a glance
- Best for women: Compressport Hurricane 10/10 Waterproof | Buy now from Compressport
- Best for men: Montane Spine | Buy now from eBay
- Best value for men: Asics Core | Buy now from Asics
- Best value for women: Finisterre Rainbird Waterproof | Buy now from Finisterre
Best waterproof running jackets for men
Best for men
Montane Spine Jacket

220 Triathlon verdict
A reliable jacket that’s great in bad weather Score: 93%
Pros
- Feature-packed
- Keeps out heavy rain
- Reflective details
Cons
- Pricey
- £250
This is an expensive jacket, but you get a fully-featured piece of kit for your cash. There’s an adjustable, wire-peaked hood, two waist adjustments and two mesh-lined pockets.
This, and the inclusion of Gore-Tex Active, all adds up to a weight of 245g (UK size medium). That being said, it also makes this the best jacket in sustained and heavy rain. The inclusion of a waterproof membrane means it’s not the most breathable, but the mesh-lined pockets help with ventilation.
There’s also a press-stud clip that sits behind the zip, which allows you to wear the jacket with the zip undone, thus boosting ventilation. Meanwhile, reflective detailing helps with visibility.
Scott RC Run WP

220 Triathlon verdict
Top performance and ventilation, but watch out for sizing.Score: 85%
Pros
- Impressive weather proofing
- Light and packable
Cons
- Sizes up small
- Zips let through some water
- £180
Scott’s RC Run shares a lot of similarities with the Rab Phantom. It’s lightweight (120g, UK large), packable and uses Pertex Shield and taped seams for its weather proofing. As a result, weather protection is similarly impressive.
The hood is similar, too, using elasticated edges to achieve a good, close fit. Though there’s no wired peak here, it still does its job well.
So what about the differences? Well, there’s a full-length zip, but this doesn’t use a waterproof zip guard on the inside, so you may find a little water ingress in sustained heavy downpours.
The other big difference is that Scott has added a series of vents to the front and back of the garment to help provide ventilation and temperature regulation. It’s a nice touch, particularly if you tend to run hot like this tester, and we noticed minimal water ingress here during testing.
An elasticated hem and cuffs help keep the elements out, but note that the fit is close, so you may want to size up.
Asics Fujitrail

220 Triathlon verdict
Everything a waterproof running jacket should be. Score: 90%
Pros
- Highly waterproof
- Great features
- Packs away well
Cons
- Expensive
- £208
It’s immediately clear that the Fujitrail is built by runners, for runners. There are two bright colourways (plus black) to help you stand out and a great set of features.
These include drawstring toggles at the hem, an integrated stuff sack, a waterproof zip pocket on the chest that’s large enough for a phone, elasticated cuffs with thumb hooks and a fully adjustable hood.
The latter has three points of adjustment, allowing you to get a close fit, but you can’t mould the hood’s peak to your liking.
Another feature I loved was the press stud across the chest behind the zip. This allows you to clip the jacket together while leaving it unzipped, helping provide ventilation while still keeping the worst of the rain off.
Speaking of which, the jacket uses a Pertex Shield fabric and fully-sealed seams to provide its weather proofing, which worked well in downpours. The jacket is also lightweight (173g, UK size large) and stashable, but all this does come at a cost.
Read my full Asics Fujitrail Waterproof jacket review.
Inov-8 Performance Hybrid
- Buy now from Inov-8

220 Triathlon verdict
Comfort and all-round performance make this technical jacket a tempting investment Score: 88%
Pros
- Extremely comfortable
- Versatile
- Practical design
Cons
- Fairly pricey
- £150 / $175
The Inov-8 Performance Hybrid doubles as an insulated and breathable waterproof jacket thanks to clever tech.
Fleecy Primaloft panels repel chilly weather while the Pertex Quantum Air outer shell provides decent water resistance.
Besides running, several outdoor activities are within the capability of the Hybrid Performance, taking the sting off the £150 price tag.
Additional welcome features include a peaked hood, snug collar and thumb loops on the sleeves.
Read our full Inov-8 Performance Hybrid running jacket review.
Rab Phantom Pull-on

220 Triathlon verdict
A superb and reliable lightweight option that’s ideal for racing. Score: 88%
Pros
- Includes portable stuff sack
- Light and breathable
- Keeps out bad weather
Cons
- No pockets
- £160
British outdoor brand Rab only entered the running market recently, but they’ve been making brilliant waterproof jackets for years.
In the Phantom we have a pared back, ultra-lightweight (89g, UK size medium) garment that packs down into a stuff sack that’s comparable to the size of an avocado. That makes it a great option for racing, when you don’t anticipate poor weather but need to bring something along just in case.
The lightweight nature of the jacket means there are limited features. There are no pockets or adjustments on the hem, but the latter is elasticated and keeps the elements out well.
The cuffs are also part elasticated, keeping weather out but allowing easy access to your watch. The only adjustment on the elasticated hood is a malleable peak, but the design means this part of the jacket actually fits nice and close.
Like Asics, Rab uses a Pertex Shield fabric here, which offers similar levels of breathability and waterproofing.
Soar Ultra 4.0

220 Triathlon verdict
Unrivalled breathability and good features, but not cheap. Score: 86%
Pros
- Good features
- Very breathable
- Water runs off
Cons
- Costly
- Not for heavy showers
- £210
Soar specialises in high-end running gear, with garments often commanding a high price tag, and that’s the case here.
The brand describes this as your ‘go-to jacket for all but heavy rain’ and in testing it shed water well.
There’s no membrane – instead, Soar applies a DWR coating to both the yarn and the finished fabric. The result is that this is the most breathable jacket on test. Yes, you’ll need to reproof it periodically, but you have to do that with most waterproof jackets anyway.
Features are also impressive. There’s no hood, but the collar fits closely, while an adjustable hem works well down below.
The cuffs are also elasticated, while a roomy zip pocket at the rear is handy for essentials but does bounce around a bit more than a chest pocket would.
It’s not the lightest (195g, UK medium) or most packable on test, but it’s not far behind the best.
Visibility is also boosted with reflective strips, while the jacket is also available in yellow and mint green.
Best value for men
Asics Core Jacket
- Buy now from Asics

220 Triathlon verdict
Light on your pocket and body, a great jacket except in downpours Score: 83%
Pros
- Very light and breathable
- Versatile
- Competitive price
Cons
- Not that well insulated
- Only water resistant
- £54
The Asics Core Jacket marries Britpop styling with low weight and breathability.
While not fully waterproof, you can’t expect a jacket costing just over £50 to be better than water resistant.
It’s also understandable that the Asics Core Jacket’s windproofing isn’t phenomenal.
But it uses elasticated cuffs and an adjustable waist toggle keep out drafts, and remains a good-value option for spring and autumn running.
Read our full Asics Core Jacket review.
Soar All Weather Jacket

220 Triathlon verdict
Few waterproof are as expensive or as effective in bad weather Score: 80%
Pros
- Superb waterproofing
- Well made
Cons
- High price
- No women’s-specific version
- £350 / $470
The Soar All Weather Jacket repels heavy rain for prolonged periods while maintaining comfort, but struggles to justify its astronomical asking price.
Fully bonded internal seams, waterproof zips and a full-length zipper guard augment wet-weather performance.
Made from a mixture of polyester, elastane and wool, the All Weather is also well insulated and breathable enough for spring, autumn and winter running.
Storage capacity in the waist and chest pockets is impressive. But such features contribute to the All Weather’s 315g weight and make the jacket hard to pack away.
Read our full Soar All Weather Jacket review.
Odlo Dual Dry

220 Triathlon verdict
A mighty jacket but there’s no avoiding that price tag. Score: 80%
Pros
- Exceptionally waterproof
- Good breathability
- Reflective details
Cons
- High price tag
- £260
The Odlo is very pricey, with the 135g weight of the Dual Dry material coming in at £1.93 per gram, close to Iberico ham prices.
So, will the ISPO-award winning Dual Dry have us (we’re sorry) squealing in delight? There’s no escaping that this is a serious rain jacket, with taped seams and a 20,000mm waterproof rating ensuring serious aqua thwarting.
Once stashed in the pocket, it’s quite hard to undo at speed, yet the adjustable hood with peak stays stubbornly in place (and stretchy hems on the sleeves and waists help prevent draughts sneaking in).
The waterproof pocket and hi-vis details add further appeal, as does the translucent material’s breathability, but whether this is £260-good will depend on your pay packet.
Montane Cetus Lite

220 Triathlon verdict
Great for deflecting rain and winds, but more for hiking than high-paced running. Score 77%
Pros
- Extremely weatherproof
- Suits hikes as well as runs
Cons
- Quite heavy and bulky
- Lacks ventilation
- £270 / $340
The Northumberland-based Montane know a thing or two about kitting athletes out for mountainous adventures, and they bill the Cetus Lite as 100% waterproof and they’re not kidding.
No matter how much I tried, even some prolonged cycling in the middle of a wet weather warning, I couldn’t get the three-layer Petrichor Technology (a recent innovation from Montane) construction’s waterproof seal or taped seams to break.
The same went for the Cetus’ pair of sizeable and easily accessible outer pockets and the full-length zipper guard, while the fully adjustable hood and waist hem also kept both aqua and chilly air at bay.
At 315g, that slightly rigid three-layer construction is heavier than many race-friendlier running-specific options and it also takes up plenty of backpack space.
The 100% nylon and recycled material didn’t leave me a sweaty mess (the Cetus has scored an impressive RET <5 breathability rating), but I’d would’ve liked some armpit vents and there are more vented and/or warmer jackets on test here, especially when running at pace.
The Montane’s £270 price might seem high but, with plenty of space for a base and mid-layer below, this is a serious piece of kit for rain-filled conditions in mountainous areas. I appreciate its versatility for a wealth of adventures on foot but, in a similar vein to the Keela with cycling, I can just see myself hiking in the mountains more than performing serious, higher paced running sessions in it. MB
Keela Saxon

220 Triathlon verdict
A versatile and well-priced jacket for both running and cycling, but not for hotter or high tempo runs. Score 75%
Pros
- Good value
- Excellent water and winf proofing
Cons
- Not very breathable
- Fit isn’t perfect for running
- £109.99 / $119
I’m between a small and medium, but the medium Saxon from Scottish brand Keela was quite roomy for me, as the images likely show.
I approve of its sensible pricing, however, while the fact that the sizeable and adjustable hood sits over a helmet gave this cycle commuting and mountain biking appeal (as does the sizeable rear zipped pocket).
The peaked hood also neatly rolls up when not in use due to the presence of a Velcro tab.
Both the ‘saffron’ and ‘morning fog’ colours are prone to showing mud, though, but the ‘morning fog’ on test here has clear reflectivity benefits. The waterproof zippers on the pockets offer plenty of reassurance, as do the taped internal seams and full-length zipper garage. The stashability is pretty good, while weight’s a lithe 260g.
Onto the main Flylite Aqua fabric’s weather-stopping abilities, and both rain and wind were dismissed with ease, aided by the Velcro fasteners on the cuffs and the waist toggle that helped prevent cold air from venturing inwards.
Where the Saxon Jacket struggled when compared to the more run-focussed competition tested here was its breathability on higher tempo runs and in warmer conditions, not helped by a lack of ventilation channels under the armpits.
The rustling of the fabric might also be a bugbear for some, and there are better form-fitting running jackets around.
I could never quite escape the fact that I felt I was running in something that felt closer to a cycling jacket, although I approve of the versatility. It certainly ticks the winter bike/run brick session boxes. MB
Best waterproof running jackets for women
Best women's waterproof jacket
Compressport Hurricane 10/10 Waterproof

220 Triathlon Verdict
I loved the waterproofed functionality here, including a little stretch and comfy fit. Score: 93%
Pros
- Ultra waterproof and durable
- Secure hood
- Lightweight
Cons
- Not a style for all
- £160
Meeting the requirements of ultra races, this jacket is constructed from 10,000 Schmerber water-resistant fabric, with sealed seams and zip combined with efficient sweat-wicking fibres.
It has an element of stretch too, which allows for a close yet comfortable fit without any annoying rustling.
The zip is slightly offset which stops the top ending under the chin and makes it easier to quickly pull open/closed.
While that hood might be giving crime-scene-cleaner vibes, it nevertheless fits snugly and is shaped in a way that doesn’t impede movement or visibility.
Like the Windproof model in our best running jackets test, this is a very lightweight jacket (102g for my size L) and balls up to fit within one hand – impressive performance for a jacket that stashes away to nothing.
Soar Ultra Jacket

220 Triathlon Verdict
Deceptively simple design that fit and performed in a way that kept me reaching for it run after run. Score: 90%
Pros
- Good waterproofing
- Breathable and lightweight material
Cons
- Not much stretch
- £190
Open a package from top-end run brand Soar, and I’ve come to expect something pretty special. As a company, their attention to detail is next level—from materials to features—and their gear quickly gets added to my ‘go-to’ kit pile.
The Ultra Jacket was no different, and while Soar has a reputation for being pricey, this actually fits well into the range here and felt worth the spend. It’s waterproof, and in testing, the rain just beaded and fell off it satisfyingly. The design uses Soar’s own ‘Rainout’ material, which is both waterproof and breathable but with a little stretch.
Added features include a rear pocket large enough for a phone (nicely positioned to avoid bouncing) and a drawstring hem. There are part-elasticated cuffs and small reflective details. I’m in an XL here (the largest women’s size), which weighed 184g.
Alpkit Gravitas

220 Triathlon Verdict
Solid performer with outstanding waterproofing and some nicely designed features. Score: 84%
Pros
- Superb waterproofing
- Eco-friendly materials
- Run-friendly features
Cons
- Bit noisy when running
- £199
With a lightweight three-layer construction and a spec list that will keep the most serious trail lovers happy, the Gravitas boasts 20K MVTR breathability and 20K HH waterproofing – which should keep most race organisers happy if there’s a set kit list.
Eco credentials are good too, with 100% recycled nylon face fabric and PFC-Free DWR treatment.
There are plenty of good additional features too, including a hood with nifty adjustable wired peak which can also be rolled away and secured as a collar, half-elasticated cuffs, a large breast pocket (which Alpkit warn may not be completely waterproof for phones) and a separate stuff pocket.
My size UK16 was light (180g) and a good fit overall. It’s a bit rustly (if that bothers you!) but worth it for the superb waterproofing. One that relishes biblical downpours!
Dynafit Traverse GTX Jacket

220 Triathlon Verdict
I can’t fault the tech and features on this jacket for serious conditions – even if it is a men’s fit! Score: 92%
Pros
- Great features and windproof
- 100% waterproof
Cons
- Big price tag
- £275
Dynafit is a brand focused on mountain endurance sports, their Snow Leopard logo a nod to their ethos as well as the Snow Leopard Trust, which the brand supports.
Sadly for me, the ‘Dawn’ colourway here is a men’s jacket (there are five colourways each for men and women), and although the fit for both is described as athletic, that explains why this jacket swamped me a bit in a medium! That aside, though, the features here were superb.
The Gore-Tex shell is 100% waterproof, and I loved the clever details, including the hood with an internal stretch band to keep it in place and a peak to keep the rain off my face.
It’s windproof yet breathable, features elasticated cuffs and hem, and has a generous chest pocket. One for the toughest conditions—I’m keen to see more from this new-to-220 brand.
Inov-8 Stormshell

220 Triathlon verdict
Supremely good in heavy rain, light and thoughtfully designed. Score: 92%
Pros
- Very impermeable
- Low weight
- Excellent fit
Cons
- Few
- £180
Weighing only 140g and extremely waterproof, the Stormshell features the kind of quality you would expect from a brand based in the fells and using some of the UK’s toughest conditions as their test bed.
Once on, this was the easiest jacket on test to forget about, fitting well and feeling barely-there. Once the heavens opened it proved its worth, though, keeping us bone dry yet not at all clammy.
The light weight and packability (it packs down inside its own zippy pocket) also made it the easiest to stash in our trail pack and forget about until needed.
The peaked hood includes a wire for adjustability as well as a cord to draw it in, plus there’s a waterproof zip with storm flap and soft fabric on the chin.
A single popper at the top of the zip allows the jacket to be held closed while the zip is open, which is a nifty feature for breathability.
At the time of writing, some colours were on sale at £140, making this jacket a great purchase.
Montane Minimus

220 Triathlon verdict
Faultless tech in the waterproofing, but fit doesn’t suit this tester. Score: 86%
Pros
- Very water-tight
- Clever details
- Packs into its own pocket
Cons
- Check the fit
- £165
At 170g this jacket from Montane’s wide range is light, plus the zippy chest pocket (which is the perfect size for a mobile phone, though Montane quote it as ‘map sized’), also has a double-sided zip meaning you can turn it inside out and pack the jacket inside.
The Minimus uses Montane’s Pertex Shield fabric with taped seams, which did a brilliant job of keeping me dry in even the heavier winter showers, while a storm flap behind the zip prevented water ingress.
Soft fabric at the top stops it rubbing on the chin and the jacket was breathable. I did find the close female-specific fit on this jacket a bit tricky – a UK12 was too small on the hips, while a UK14 felt baggy overall.
Less curvy runners may find it suits them better, though a wider hem with more adjustability (you do get a drawcord) would give wider appeal. A wire peak on the hood along with an adjustable cord make sure the hood stays in place, plus you get reflective details.
Read my full Montane Minimus Lite review.
Alpkit Gravitas

220 Triathlon verdict
This was one jacket that we enjoyed using every time. Score: 88%
Pros
- Great waterproofing
- Impresisve spec
- Reasonably light
Cons
- Waterproofing of front pocket isn’t guaranteed
- £179.99
In a sea of muted blues and greens (we didn’t plan that!) this brighter ‘Fontainebleu’ option instantly put a smile on this tester’s face, something that carried through into testing too.
At 185g it is lightweight and felt barely-there, with very little rustling. The features include a large pocket on the front (though Alpkit advise caution, as they cannot guarantee waterproofing) and a wire peak on the hood, albeit with a nifty elastic adjuster and toggle on the top here, which allows you to pull the hood back to stop it obscuring your vision.
A hood stow tab also offers an easy way to roll it up when not needed. Cuffs are not adjustable, though an elasticated portion worked well and made them easy to push up if we got too warm.
The waterproofing was excellent with Alpkit’s highly breathable and waterproof (and recycled!) fabric doing an admirable job of keeping us dry. Taped seams and a storm flap behind the zip also feature, plus a stuff sack.
Best value for women
Finisterre Rainbird

220 Triathlon verdict
A technical jacket with eco-credentials and a reasonable price point.. Score: 88%
Pros
- Good shower protection
- Effective sweat wicking
- Eco credentials
Cons
- Few
- £125
Built from 100% recycled fabric with eco-friendly, flurocarbon-free waterproof coating, the Rainbird has the kind of credentials you’d expect from B-Corp pioneers Finisterre.
Out on our test runs it kept us dry in both light and heavy showers, while breathability was excellent. Taped seams and a waterproof zip with storm flap and soft-touch fabric on the top added to the snug, dry feeling.
Large pockets with flaps were a good size for essentials, while toggles and draw cords at both the hem and around the hood allow for good adjustability, and once drawn in the hood was a snug fit around the face.
Like the Montane, Velcro on the cuffs allows the sleeves to be adjusted and prevents water ingress on the wrists.
The little bit of stretch in the fabric was appreciated and the jacket felt high quality, while the microporous inner film did a good job of wicking away sweat. Five women’s and seven men’s colours are available.
Best for women
Salomon Bonatti Trail

220 Triathlon verdict
High quality, weatherproof and completely reliable. Score: 94%
Pros
- Super weather protection
- Excellent spec
- Packable
- Smart design
Cons
- Expensive
- £200
Light, breathable and packed with subtle features to set you up for a comfortable run, the Bonatti Trail is the priciest jacket in the women’s test.
So we were keen to test it to its limits in the torrential English rain and see if it’s worth the cash. Impressively, it does a great job fending off wind and rain, even in sustained, heavy downpours.
It fits well, too, with a secure hood, elasticated cuffs, waist adjustment and a drop tail at the back. Meanwhile, a press stud fastener behind the zip allows you to keep the zip open while maintaining weather protection, which is great for ventilation.
At 167g (UK small), it’s light, portable, and packs neatly away into the only zip pocket on the chest when not in use.
Read my full Salomon Bonatti Waterproof jacket review.
Omm Halo

220 Triathlon verdict
No-frills design for when functionality is key. Score: 85%
Pros
- Featherweight
- Staunch waterproofing
Cons
- No pockets
- Minimal adjustability
- £100
Designed to pack up small and weighing just 99g, this jazzy jacket boasts taped seams and two-layer 10,000mm HH fabric to keep us bone-dry in heavy downpours, while the female-specific fit and dropped hem are nice touches for keeping our bum dry.
It felt less warm than the Montane or Inov-8 and is also the only jacket on test to make a rustling noise as we ran – you don’t really notice it so much in rainy conditions.
There are no pockets and the hood isn’t adjustable, but it fits snugly round the head with an elastic peak and elastic cords adjust the hem and it meets all the requirements for essential race kit.
Grey and grey/purple colourways are also available if pink isn’t your thing, although we liked the touch of neon pink for safety.
How we tested the best waterproof running jackets
Experienced 220 Triathlon gear testers Rob Slade, Matt Baird Helen Webster have reviewed the waterproof running jackets in this list.
All our reviews are 100% impartial and we put in the testing hours in our training and races.
Above all, of course, they tested the jackets’ waterproofing by seeking out showers. Besides evaluating the effectiveness of the waterproof membrane, they assessed how well the zips and seams kept out water.
Breathability is important too because you don’t want to get wet on the inside of a poorly ventilated jacket.
They also judged how light and packable the jackets were – portability is important when you’re running long distances in variable conditions.
Jackets with extra features like pockets and hoods got credit too. It’s ideal if pockets have waterproof zips and can fit things like keys, phones and snacks.
Rob, Matt and Helen considered the jackets’ visibility and reflectivity as well. When it’s wet, it can be dark too, and being seen is always a good idea.
Lastly, they took into account value for money by assessing the jackets’ performance relative to their price.
What makes a jacket waterproof?

Most waterproof running jackets will use either a waterproof membrane, a durable water repellent (DWR) coating or a combination of both.
That membrane is usually bonded to the inside of the jacket, which will form part of a two or three layer (or sometimes 2.5 layer) system. Often, these membranes are provided by a third-party company such as Gore-Tex (widely regarded as industry leaders) eVent and Pertex.
DWR coating
Brands typically then apply a DWR coating to the outside to ensure water beads up on the surface of the jacket.
The DWR coating will wear away over time, particularly when it gets dirty or is faced with a lot of abrasion, such as from a running pack.
When that happens, the outer fabric may ‘wet out’. That means that water soaks into the fabric on the outside of the jacket, though doesn’t go through the membrane (if the jacket in question has one). As a result, the jacket can start to feel cold, heavier and breathability can suffer.
To avoid this happening, DWR coatings needs to be reapplied periodically with a special wash or spray, such as Nikwax or Grangers.
For a jacket to be truly waterproof, its seams need to be sealed. This typically comes in the form of taped seams, which stop any water from passing through.
Hydrostatic head
When looking at waterproof running jackets, you’ll probably see a figure (in millimetres) quoted in the product description. That’s probably the hydrostatic head (sometimes written as HH), which measures how waterproof a fabric is.
To be classed as waterproof, a fabric should have a minimum rating of 1,500mm, though most waterproof kit will typically have hydrostatic head ratings of 5,000m upward, and most waterproof jackets will have a rating of 10,000mm. That last figure is a good benchmark when searching for your jacket.
What about zips?
One final note… due to the very nature of them, zips are rarely described as 100% waterproof. Many utilise DWR coatings and waterproof materials in their construction, and do a fine job of keeping the elements out, but they can still be a weak point in weather protection when in particularly bad conditions.
As such, we like to see a storm flap behind the zip to protect against any water ingress.