I spent ten years in Calgary, and just recently moved back to Ottawa. My brother currently lives in Fort McMurray. Huge difference in climate.

My guess is you're going to be working in Fort Mac. If so, you can expect temperatures of -30 or -35 on a regular basis in the winter, occasionally -40, but it can be quite warm in the summer. (They are currently undergoing a heat wave, with temperature of +30C expected for the weekend.)

My brother used to live in places like Slave Lake and Peace River. I visited them once in Peace River when the daytime high was -35; you could actually feel the resistance when you opened the car door. Apparently, it was not uncommon for residents to leave their cars running in the parking lot all day while at work because if you shut them off, there was no way to restart them (short of towing the car into a heated garage and letting it thaw out).

Block heaters for cars are virtually standard issue on any cars sold in that part of Canada; make sure you plug them in overnight during the winter to keep the engine warm. A new car will start okay even in temperatures of -30, but not using the block heater will significantly shorten the life of the engine.

Don't be misled by any stories of "it's a dry cold, you won't feel it". It doesn't get bone-chilling cold as a maritimer would feel it, but trust me - you will know it's cold.

The first time my brother (brought up in Nova Scotia, where it's a "damp cold") experienced a really cold day in Peace River, it was a real eye-opener for him. He ran out in his shirt sleeves to start the car, so it would be warmed up by the time he finished his breakfast. By the time he got to the car in the driveway, his fingers were so numb he couldn't unlock the car door. By the time he ran back to the house, his hands were so cold he couldn't turn the door handle; he just kicked the door until my sister-in-law came running and let him back in. Never made that mistake again.

The upside to the "dry cold" is that it doesn't seem to penetrate the houses - once you're inside a warm house, it's quite comfortable - as opposed to some places where, no matter what the thermostat says, it just feels cold to the bone because it's so damp.

Fort MacMurray, where the oil sands are, is about the same latitude as Peace River and Slave Lake, so probably gets about as cold in the winter.

Having said that, your main difficulty is likely to be finding a place to stay - the housing crunch there is unbelievable. When my brother first moved there, he spent the first six months renting a 3-bedroom trailer - with his wife and four children.

Also, because the cost of living is so expensive, people can't really afford to work in the service industry (waitresses, cashiers, etc.) unless they have a family member working in the oil fields. This means that the level of service in a lot of places isn't what you might have come to expect. (The typical job interview goes something like this - "Can you start tomorrow?")

The prices in clothing stores, from what I could remember, weren't outrageous. (Edmonton was about a five hour drive, so if the prices got out of hand, people would simply schedule a shopping trip down south.) but the "Work Warehouse" type stores didn't sell the same designer clothing that they do down south - the stuff they sold was for the people working out in the oilfields, so it had to be functional.

For going out after work - in town, wear regular clothes, with a good parka and a tuque or watch cap; perhaps with mittens, heavy wool socks and boots if you expect to walk more than a block or two outside.

Of course, if you're talking about Inuvik or Tuktoyaktuk, that's a whole different story again. :-O