For Opera 15 and above a new version available - https://addons.opera.com/en/extensions/details/gismeteo/
The icon in your toolbar displays real time weather or forecast for the nearest time of your favorite place. Click the icon and you will get detailed forecast for 24 hours.
You can make your own design by changing icons set and color themes!
Absolutely new easy-to-use interface and easy configuration
Toolbar icon displays real time weather or a forecast for the nearest time
Real feel temperature
New skins and new two icon sets