One of the most important things about choosing the proper clothing for working outdoors in the winter is knowing what you're up against. The type of job you're doing can make a difference between needing a bomber jacket or parka, simple rain pants or insulated bibs, or the difference between needing an ANSI or Non-ANSI garments for visibility. For example, while a bomber jacket usually offers a higher level of mobility than a parka, the parka will usually tend to be warmer than the bomber jacket.
There are several factors you should consider before deciding which garments have the proper features to meet your needs and help simplify your job duties. Does your job require working in rain or in/around standing water? Is high visibility ANSI compliance a necessity? Can hands-free communication or a radio pocket make your job easier? Are you working in sub-zero temperatures which requires garments with heavier insulation? Can you open or unzip the pockets without needing to remove your gloves? Properly identifying your needs will make for a better performing and more functional purchase.
Quality should also be a concern when making a purchase. If you're only working a temporary job or don't need the added cost of a high quality jacket, there are plenty of economical options available. On the other hand, if your job consists of long days, exposure to extreme cold or requires working with heavy materials, you might consider something made with heavier insulation, ripstop fabric, a heavy hood, and a design that eliminates wind & water penetration. It's also important to determine whether you'll be near exposed flame, fire, or sparks and if you'll be safest with FR-rated fire resistant garments. Convincing yourself that you can get by with the cheapest ANSI 2 jacket available doesn't mean your workday will be much warmer or any easier. If you'll be spending several months working in the cold, you'll need to be prepared so be sure to choose the products that will offer you the highest level of comfort and functionality for your specific duties and profession.
Last but not least, don't rule out the effectivity of accessories such as hats, gloves, and other insulating products. While a cheap pair of hardware store work gloves might prevent frost bite, they're not going to stand up to the elements or the repeated handling of heavy materials such as stone or metals. Your best bet is to find something that not only keeps your hands or head warm but is also durable enough to survive the season, is available in high visibility colors, and provides a secure fit.
Again, you get what you pay for and while you don't need to spend a small fortune to protect yourself while working outdoors in the winter, it's helpful to think realistically and make sure the garments you purchase are sufficient for delivering extended warmth, safety and comfort, all day long.