About 10 years agoin the middle of January, I remember a couple of crew members talking about cold temp. corrections for the arrival. There happened to be a chief pilot (from one of the mexican airlines) sitting in listening, after a few minutes he politely asked if he could look at the chart. When he did read the chart his face went white and he then asked if he could make a copy to take back home. Seems they were far below the published altitudes. The airport Kelowna BC and the temps were around -20c on the ground.