A frigid winter is predicted for the northern hemisphere. Blame it on the number of new moons, is what I've heard. Locally, snow does seem to be sliding down the mountains like a cold, sleepy eyelid.

Harder to forecast is what cut and colour of winter coat to buy. Hem length is always an issue, but this season there are different sleeve lengths too, including tempting, vintage-evocative three-quarter looks. If you don't want to dump your barely worn purchase in the thrift-store bag come spring, you should keep certain design details in mind.

Armholes need to be cut with enough slack to accommodate sweaters. Wear one when you trawl the stores, or at least take one into the fitting room with you. Logic also suggests that wrap styles also unwrap, that you need to be built like a Q-Tip if you want to wear anything belted, and that coats with a deep V-neck won't keep you as warm as ones with a collar that buttons up to your chin.

You need a style that's in tune with the rest of your wardrobe–or at least most of it–and pockets with enough room for gloves or cold hands; this is all just common-sense stuff. Think hard about single- versus double-breasted. A single-breasted cut looks swashbuckling if you wear it open; doing this with a double-breasted coat gives the impression that you've forgotten to button it up. Then again, when it's frosty, how often do you walk around with your coat undone?

I'm a firm believer in browsing through shops that are way beyond my budget, just to tune my eye to shape and colour. At Bacci's (2788 Granville Street), Andreas Melbostad–the Norwegian designer behind the Phi collection from New York–has completely rejigged the classic duffel coat, erasing all its '50s art-student connotations and creating an ultra luxe version in navy wool. He's kept the traditional roominess, toggle fastening, and hood, but added vertical seaming and patch pockets in leather ($2,095). Black satin edges the pockets of a Phi above-the-knee coat ($1,495) that gently references military lines–though I've never come across a uniform cut from navy alpaca that looks like sheared fur. Lucky you if your credit card doesn't wilt in disbelief before these, or when faced with Belgian designer Dries van Noten's takes on toppers. Eyeball with longing his black patch-pocketed, smock-cut coat that hits just below the knee ($1,720), or his zip-front, flawlessly simple coat in a tweedy charcoal or studious brown ($1,280), like something an improbably elegant, female Henry Higgins might don.

Back in the land of reality, Plum Clothing (various locations) has zeroed in on the pea coat. Over jeans or winter's must-have Crofton House–style plaid mini, this classic double-breasted piece by designer Claudia Agusti (on sale at $192, made in Vancouver from Italian fabric, and lined for warmth) is tops for versatility; take a boo at www.plum.ca/. If it's sold out, try another of her designs that channels Jackie Kennedy with an above-the-knee style in a warm cream or black plush fabric (on sale at $155). With its pretty pleated collar, it's charmingly retro right down to its three-quarter-length sleeves. Those sleeves mean the wise won't walk out of the store without grabbing a pair of long knit gloves ($14 or $16), available in all kinds of neutral and bright colours; my money is on the ones trimmed with eight petite pearl buttons.

Cropped coats of different colours hang around at Gap (various locations), cut from what looks like boiled wool, a felted texture that gives it a Tyrolean vibe–Heidi ho. Black takes you anywhere, but looks increasingly unadventurous. Fashion-forward though it is, I'd avoid reaching for grey, which, if January stays true to form this coming year, will not put you in a happy place unless you zap it with patent accessories, preferably in scarlet. Instead, opt for the cheery red or shamrock green, or navy if you're timid, all with black buttons ($98). Only the sleeves are lined, so make sure there's room for a sweater underneath. Going even wilder, prowl around Sears (various locations) and you may be fast enough to snag a zebra- or leopard-print mid-thigh-length coat ($99.99, and it reverses to solid). Move on to Zara (various locations), and you get a glimpse of the coats worn on the streets of Paris and Madrid. Carrying the Zara Basic label is a double-breasted high-buttoning coat (almost all coats button high this season) in black, white, or vivid red or orange, all with black buttons ($99.90).

Eye-rocking colours just don't grab you? Club Monaco (various locations) stocks a luscious knee-length style in black ($389) that hits all the marks: funnel collar, smock-inspired cut, and sleeves that widen at the elbow and narrow at the wrist. If you've nabbed three-quarter-length sleeves, the store sells delectably soft elbow-length cashmere gloves in berry red, two shades of grey, and winter white ($79). If these aren't on your Christmas wish list, they should be.