I was told that ATC in those areas that experience cold weather have already made allowances for the lowest temps thus intermediate altitudes need no correction. Or they will add to the published altitudes on extra cold days. However I have not seen any additions when I have flown in these conditions (never had a GPWS under these conditions either).
And yes, there are some of us who think a bit deeper and so will disagree!
If you add to your published altitude, tell ATC. If not you risk reducing separation.
On cold days on the field (which is the only place the correction will be accurate) it is not necessarily cold at altitude. Lapse rates vary, and inversions are possible even in cold climates, so a correction will not necessarily be required at intermediate altitudes. With modern airplanes you can check this, since the airplane can give you true outside temp all the time. Before making changes, check it! If you add a hundred feet to the minima when the temp above the field is actually close to normal, you risk an unecessary go around. OK if you have the fuel I suppose.
Far better in my mind to use the radio altitude to confirm the pressure readings. Knowledge of the terrain would be needed, but most pilots who operate into these conditions know their area well. Good pre planning will prevent surprises. The procedure in the Jep is simplistic and should be used with common sense. It will give you a rough correction but might replace one problem with another. Next time you go to one of these places, note the true OAT at various points and see for yourself. You will see that the temp on the ground is quite often much lower than it is in the air, especially above 2000 feet agl.