Most of the time I see sex workers represented in the media, they’re wearing short shorts and fishnets or something equally provocative. What do they wear in cold weather? It’s hard to imagine looking very sexy in a hat and mittens. Do they get frostbite?
When I was in the Las Vegas area in the winter there were two women near the hotel in very short skirts. It was quite cold and they looked like they were freezing. So in at least one case they wear what they normally do I would guess.
They wear the same stuff IME. Simply suffer – problem solved!
…but I’m thinking of places like London in winter. I don’t know about, say, Moscow.
As an aside, one time I was in Barcelona and there were prostitutes around during the day. In the middle of summer. It occurred to me that with their stockings and other accessories, their outfits were less revealing than what most other women walking around were wearing 
With the right heel and short skirt, leg warmers can be quite alluring. Add a cropped “leather” or “fur” jacket and you’ll survive most nights in Chicago. You won’t be exactly comfortable, but you’ll probably survive.
Long johns ?
Long-johns.
ETA: shakes his johnson at Themenin
No, but they do get chapped lips.
Seriously, in Ottawa in the winter they wear what they normally do, except with knee boots, winter coats, and gloves.
We have boring hookers round here- they tend to wear jeans and a jacket most of the time- often with heels and a short top under the jacket, but still; C for effort.
Therma-Thongs™ :D.
The OP is supposing that all sex workers are street walkers. Thats probably a small percentage of sex workers. Most sex workers start and end their shifts inside a comfortable heated workplace and get changed when they arrive.
Man–your prostitutes suck!
Yup. Less to take off.
they get regular and wide stick lip balm.
I’m glad you asked.
Hoboggans.
(aka prostituques)
Therma-Thongs with Thinsulate. 
One of my favorite wise cracks - a friend of mine as we were driving down Hennepin Avenue one winter evening, and he glanced out the window at the ladies of the evening plying their trade:
“Minneapolis - the only city in the world where the hookers wear galoshes.”
Regards,
Shodan
That is sort of the point, yes.
To the OP: in a lot of northern cities, as Filbert pointed out, prostitutes don’t dress nearly as skimpily as TV would have you believe. When I lived in Erie, PA (a festering cesspool of such things perhaps one level below New Orleans and Vegas), I read a newspaper article about how sex workers signaled their availability. It was a subtle code of eye contact and other nonverbal communication. If a john driving a car made eye contact with a woman in a high-prostitution area and she held it, that was the indicator. She would then turn the corner and walk slowly, essentially waiting for him without being painfully obvious. If he came around to meet her, she’d approach, and they could get down to business. In other words, the average person walking or driving by would never notice anything out of the ordinary if they weren’t clued in. Being the clueless type myself, I was stunned to find out that I had been driving through a major area for that sort of thing nearly every day.
That’s my experience as well. Most streetwalkers aren’t identified so much by their skimpy clothing as by their swagger when they walk and unrelenting eye contact as you drive by.
Really wishing for a “Like” button on the boards right about now.