Yeah they work turnarounds here and a lot are in winter, but it's not that cold. The biggest of the 3 B's I worked (something Broke down, something Burned up, something Blew up) it was about 2F in Baton Rouge on Christmas eve and a valve stuck/let go coming off a tank. Big boom that leveled a large number of houses and buildings, Exxon bought the land and it now a wildflower planted area lol. But on the gulf coast fall and spring turnarounds are normal times and it's not normally that hot or that cold. But when something breaks in my experience shit never goes wrong on a sunny 75F day at 2 in the afternoon. It does at 2am when it is cold and raining.
But the guys that are electricians that actually work for Exxon and not a contractor they almost always work in the maintenance shop and like I mentioned it's heated and cooled which is nice. When I worked in San Antonio their shop was cooled for large plate fabrication and all those shops have a full time electrician to keep the heavy machinery going and they rarely work overtime other than when something breaks. It's not a regular thing like some industries that work 60 hours a week every week. Of course I have noticed the guys that are working there that are electricians kind of get roped into doing other thit all the time as well. Not hard work, but they might wire up a light for a crawfish table the owner had made.