That's a true barb expert there, no condition will stop you!!!
4 years ago we had a freak winter windstorm. The outside temp was -46 degrees C with a 100+ kph wind and that managed to stop me.
For you non-metric folks, that's below -50 F with a 60 mph wind. The wind chill guide said it "feels like" -106 C (-158 F). Propane won't even vaporize properly at that temperature. In fact, I stepped outside on that day for 90 seconds, and it took less then 30 seconds for my exposed skin to freeze.
So yeah, there are days I won't grill for any reason.