SP Weather, a free weather extension for Joomla 2.5 and Joomla 3.x, use Yahoo Weather as API. You can display the weather of your place by two provided designs, as block or as list. SP Weather integrates Celsius and Fahrenheit as temperature display. A lot of settings can be configured directly in Joomla Backend. JoomShaper provide this module extension on their website. You can download it without conditions.