This is the software publisher's description.

Firefox extension that brings international weather from AccuWeather.com to your web browser. You can use your US zip code or you can easily find your town or city by using the built in search tool. It is unobtrusive and lightweight, yet can be customized to display nearly as much data as the leading desktop weather programs! If you can't find what you are looking for, click the weather icons displayed to open the AccuWeather.com forecast for your location. A slider, similar to when popup notification for when all downloads complete, pops up from the bottom right corner of your screen when the current conditions are updated. You can even set what appears in it or disable it!

Forecastfox lets you customize everything, from the number of days to be forecasted, to the content of the tooltips. You can decide whether to see the labels, and you can decide what toolbar to place Forecastfox in. The options window is intuitive and makes it fast and easy to change any of the settings you'd like.

The profile system lets you easily change between multiple locations. Each profile saves all of its own settings, including the tooltips and labels, the number of days forecasted and the location of the forecast. There is even a setting that allows you to automatically rotate between the profiles at a given time interval.