Interesting question. My therapist charges the fee for the session if it's cancelled by the client less than 24 hours in advance and offers a free session if he's the one to cancel less than 24 hours in advance (I didn't agree to this when he suddenly wanted to make this rule out of the blue after a year of me never canceling less than 24 hours before, so we don't do that, but I know that generally this is his policy). I don't know if weather is considered an exception, but unless it was extreme weather conditions with absolutely no way of going out, it should be no exception in my opinion. I wouldn't change this policy on account of cold or a storm, myself. Sure, it's inconvenient, but it's not impossible or dangerous to travel, and with all the weather forecasts it's also not impossible to know beforehand whether or not it will be okay for one to go to therapy that day. Now, if the temperatures were so low or hot that it would be a very serious risk to go out in any way, I would find it a different situation and it would be reasonable, I think, for any therapist to be understanding of that.

That said, all of my sessions were held no matter the weather. Neither my therapist nor I have ever canceled a session shortly before the scheduled time due to weather. There was only one time when I was visiting my parents in a different city and there was a lot of snow, the trains were greatly delayed (there was even a whole 24 hour delay in one particular case), and I canceled - but I was also dissatisfied with my therapy in general at the time, and I gave him a fair notice anyway, let him know two or three days before the session.

I'm very curious to read everyone's answers.