If time is important to you, don't use Forecastfox Rated 3 out of 5 stars
I like Forecastfox, but when opening a window it causes everything to load so very slow. It's not worth it to me to have to wait on Forecastfox to load and then be able to access my pages. I've used it for some time and until it started doing this, I was more than happy with it. But now, I've uninstalled it. It also caused pages to be slow when it updated as well.
At times it would state the weather was sunny when in fact it was raining or vice versa but that's normal for this area. I don't need something to tell me if it is sunny or cloudy. I can look out my window for those facts. I'm mainly concerned with the radar and the temp.
It's really sad that the problem of causing Firefox to be slow caused me to stop using this extension. Fix that problem and I might use it again. I used to recommend it to others but now, not so much.