Hi Ellyn,
I think I'd be rather upset, too.

Out of courtesy, I'd certainly always notify my doc well in advance if I have a real need to cancel an appt, however reasonable notice is not always possible. And likewise, I expect my docs to have in place reasonable policies that I'm made aware of in advance.
I understand their interest and need to discourage last minute cancellations, but every employer out there faces lost productivity/revenue due to illnesses and storms and that's just one of the costs of doing business. My GP has a policy of charging a nominal fee if not given 24 hrs notice/ or in absence of a valid reason. I once had to cancel with my GP, as that day I had an iritis attack and you take whatever appt you can get when the Ophtho is kind enough to squeak you in. Murphy's Law that it would overlap with my GP appt.

Kindly, they didn't charge me, and were perfectly understanding about my predicament.
Rheumies (over anyone else on the planet) should have a deeper understanding for how difficult it can be for us spondylitics to venture out in pain and in midst of a snowstorm. The recent snowstorm in T.O. equated to > 400
+ car accidents in the span of a few hrs! Personally, I don't go out in serious weather unless I must.
I sure hope your Enbrel will not be interrupted by this.
mig