Which Jacket to Choose for Autumn and Winter?

In mid August the mornings drop to thirteen degrees while the afternoons hold twenty five. Choosing a jacket starts from that spread, not from a shape: settle the temperature range first, pick the cut second. The reverse order ends in a jacket worn three weeks a year.

Where do you start when choosing a jacket?

A jacket is chosen against three numbers: the lower and upper temperature limit, the number of layers underneath, and the length at which it finishes against the hip. The cut follows from those three things rather than leading them.

The temperature range decides the filling and the weight. From 15 to 22 degrees a single layer of fabric with no insulation is enough. From 8 to 15 degrees you need a light filling or a dense weave. Below 5 degrees only insulation and a tight closure at the neck and wrists still matter.

The second number concerns what you wear underneath. A jacket bought to go over a sweater needs roughly five centimetres of room across the shoulders and under the arms compared with your usual size. Without it, a heavy knit presses out the sleeves and compacts into a stitch that stays flattened permanently after a few weeks.

Which jacket shapes are worth knowing?

Eight shapes cover the whole year, and each of them has a narrow temperature range in which it genuinely performs best. The table below sorts them by that range rather than by popularity.

Two rows from this table are most often bought without regard to their real range. A down jacket is irreplaceable below zero, but at five degrees it causes overheating and moisture underneath, which takes its insulating properties away. A bomber finishes at the waistline, so over a low rise bottom it exposes the midriff and protects nothing, whatever its weight. Across jackets it is best to start from the transitional range, because that is the one covering the most days in a year.

Which jacket keeps you warmest?

Warmth is decided by the amount of air trapped in the filling rather than by the thickness of the jacket. Goose down has the best ratio of insulation to weight, but it loses that once wet and needs a dry environment.

• Natural down. The warmest at the lowest weight, right for frost and dry air, and it stops warming once soaked.
• Synthetic filling. Heavier for the same insulation, but it keeps working wet and dries several times faster.
• Quilting with no filling. Only a layer of air between the seams, good to 10 degrees and no lower.
• Wool and wool blends. They insulate even slightly damp, but they let wind through, so they need a windproof lining.

When buying, check the three places most heat escapes from: the collar, the cuffs and the lower edge. An elastic or an adjuster at each of those points makes more difference than another hundred grams of filling. What is missing most often is adjustment at the hem, which lets warm air out with every step.

Which jacket works in the rain?

In rain what counts is the surface finish rather than the material itself. Coated cotton, membrane backed polyester and the classic gabardine of a trench all shed water for as long as the treatment is fresh.

A trench remains the best answer at above freezing temperatures, because its storm flap carries water past the shoulder line and the vent at the back lets you walk without straining the fabric. Densely woven gabardine looks matte and slightly grainy in daylight and falls vertically in movement instead of breaking, which is why pieces from coats in that weave look right even when wet.

Water repellent treatment wears out after a dozen or so washes and is worth renewing each season with a spray for technical fabrics. You will recognise the wear when water stops beading and starts soaking in as darker patches.

Which jacket length suits which figure?

The lower edge of a jacket creates the strongest horizontal line in a whole silhouette, so it should not fall at the widest point. That is the single rule from which all the others follow.

A jacket finishing at the waist visually lifts the waistline and lengthens the leg, but it needs a high waisted bottom. A hip length model is the safest, because it suits any bottom and sets no conditions for the rest of a look. Mid thigh shortens the leg, so below 165 centimetres a straight cut works better than a flared one. Anything below the knee already belongs to a different register and follows a different logic of proportion.

What tells you a jacket is well made?

The durability of a jacket is settled in four places that take the most load: the zip, the underarm seams, the lining and the pocket finish. The outer fabric is usually the last thing to fail.

Test the zip by running the slider down and up with one hand, without holding the lower edge. A good metal zip does not jam and needs no guiding, and a plastic one should at least move evenly along its whole length. Inside, look at the underarm seams: a double row of stitching or a reinforcing tape shows the manufacturer allowed for shoulder movement, while a single row will open within a season.

The lining says the most about hidden cost. Viscose and cotton breathe but wear through faster, polyester lasts longer and holds moisture in exchange. In a jacket worn daily, resistance to abrasion around the pockets matters more, because that is where hands work most often. Check whether the pockets have a reinforced base, because that is the most common place a jacket stops being wearable while the outside still looks new.

Assess the weight separately. At the same declared insulation, a lighter jacket means a better filling, so if you are torn between two models, pick both up and compare the weight before you look at the label.

What not to pair with a jacket

Three mistakes repeat regardless of the shape, and all of them come from ignoring the layer underneath.

• Do not buy a jacket fitted at the shoulders if you plan to wear a heavy knit under it, because the stitch compacts in the sleeves and loses its spring for good.
• Avoid pairing an oversized jacket with a full bottom half, because two loose layers blur the waistline and shorten the whole silhouette.
• Never zip a down jacket to the neck above five degrees, because moisture condensing underneath takes the insulating power out of the filling for the rest of the day.
• Do not wear a short bomber with low rise trousers, because the exposed gap between layers splits the silhouette exactly in half.

Which jacket suits the turn of summer into autumn?

For the turn of August into September the best answer is an uninsulated layer you can take off and roll up: a shirt jacket, a denim jacket or a thin quilted piece with no filling. With a spread from 13 to 25 degrees within one day, what counts most is whether the piece fits into a bag.

A shirt jacket is the most flexible answer here, because it plays two roles: fastened it replaces a top, open it works as a light cover. Choose cotton or a linen blend, because synthetics at twenty five degrees hold moisture against the skin, and pieces from linen and muslin handle that range best. The alternative is a piece from denim, which covers the same range but takes rain less well and dries more slowly.

Frequently asked questions

Which size should you take when torn between two?

Take the larger one if you intend to wear anything thicker than a top underneath. The allowance is measured across the shoulders and under the arms rather than at the waist, because that is where a lack of room restricts movement and damages the layer beneath.

How does a parka differ from a down jacket?

A parka is longer, has a hood and a cut that narrows towards the hem, and its filling may be either down or synthetic. A down jacket describes only the type of filling and comes in any length, including a short one to the waist.

Can a down jacket be washed at home?

It can, in a machine, on a delicate programme at 30 degrees and with a down detergent rather than powder. What matters is drying with three tennis balls in the drum, because without that mechanical breaking up the down clumps and the jacket loses insulation for good.

How many jackets are enough for a year?

Three, one for each temperature range: a transitional one with no insulation, an autumn one with a light filling and a winter one for frost. A fourth only makes sense if you need a separate piece for rain or for occasions in a different register. With three, though, it is worth making sure all three fit over the same piece from sweaters, because the middle layer moves between them most often and it is what forces the allowance at the shoulders.

Come back to those thirteen degrees in the morning and twenty five in the afternoon. There is no single good jacket for a day like that, but there is one good strategy: a thin outer layer you take off by ten, plus a knit in your bag for the walk back after dark.