Google has just launched a nifty new weather layer for Google Maps that provides you with current weather conditions from around the globe generated by the U.S. Naval Research Lab. This will definitely save you the frustration of jumping from Maps to your current weather app of choice when planning your next excursion.
You can click the icon for any given city to get a four-day forecast and more detailed data including wind and humidity conditions. In the left-hand pane, you can select temperature(F/C) defaults, wind speed (km/h, mph, or m/s), and optionally “hide clouds”.