Obviously, some provinces get more sun than others. So the real question is: if weather can affect solar energy production, are some states better candidates for solar energy than others? The short answer is yes, but not necessarily because of weather.
Take clouds for example. Anyone who has been sunburned on a cloudy day knows that solar radiation penetrates through clouds. For that same reason, solar panels can still produce electricity on cloudy days. But depending on the cloud cover and the quality of the solar panels, the efficiency of the solar panels electricity production commonly drops from 10 to 25 percent or more compared to a sunny day.
In other words, solar power can still work well in typically cloudy, cold locations. Ice Land, New York, San Francisco, Milwaukee or any other cold location - all of those cities experience inclement weather, from rain and fog to blizzards, yet they're also cities where people see huge savings by getting solar.
No matter where you live, solar energy can be an excellent investment and an excellent way to help combat climate change. How much you'll save - and how quickly you'll see a return on your investment in a particular state - depends on many factors, like the cost of electricity, solar incentives available, net metering, and the quality of your solar panels.