In my opinion, American immigrants are always welcome in Canada. I've made the acquaintance of many fine Americans over the years.
In all honesty, there are tensions between our two countries. Part of it stems from what some Canadians view as an unfair application of the North American Free Trade Agreement (to the detriment of Canada).
However, I think you'll find most Canadians open minded and friendly.
As for the warmest place in Canada, opinions vary as to the exact location, but the province of British Columbia seems like the clear winner. For you, that means staying on the west coast!
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