The latest version of Google Weather - v1.7.7 - now allows you to show the wind speed in km/h.
If you display the temperature in degree Celsius, the wind speed will be displayed in km/h. If you display the temperature in degree Fahrenheit, the wind speed will be displayed in mph.
Note: By default, Google only returns the wind speed information in mph. I used the PHP function preg_match() to search for the string "mph". If you have displayed the weather information in other languages (e.g. Russian) which does not display miles per hour as "mph", the module will just display whatever wind information that is returned by Google.
Download here: http://extensions.joomla.org/extensions/maps-a-weather/weather/weather-forecasts/10274
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