Abstract: Systems are provided which enable a method which includes determining the location of a particular mobile device and collecting location data corresponding to a plurality of mobile devices within the particular geographic area, the geographic area defined based on the location of the particular mobile device. Weather data corresponding to the plurality of mobile devices is collected based on sensor measurements from the plurality of mobile devices. A weather condition is determined based on the location data and the weather data corresponding to the plurality of mobile devices, and the weather condition is reported to a user of the particular mobile device. Other methods are provided in which one or more user-provided indications of comfort corresponding to one or more determined weather conditions are used in determining a level of comfort corresponding to a particular weather condition for the user.