If you like to check out your local weather in the Panel, you are in luck. Ubuntu ships with a Weather Indicator application. It shows the current temperature in the Panel and also indicates the weather by means of a suitable icon. On clicking it, you can view other details like forecast, humidity, sunrise and sunset times.
This application can be installed from Ubuntu repositories using the package name indicator-weather. Once installed, it can be launched from the Dash with the name Weather indicator.
Tried with: Ubuntu 12.04.2 LTS