google-weather-icons

http://www.gstatic.com/images/icons/material/apps/weather/2x/wintry_mix_rain_snow_light_color_96dp.png

http://www.gstatic.com/images/icons/material/apps/weather/2x/haze_fog_dust_smoke_light_color_96dp.png

http://www.gstatic.com/images/icons/material/apps/weather/2x/cloudy_light_color_96dp.png

http://www.gstatic.com/images/icons/material/apps/weather/2x/snow_showers_snow_light_color_96dp.png

http://www.gstatic.com/images/icons/material/apps/weather/2x/flurries_light_color_96dp.png

http://www.gstatic.com/images/icons/material/apps/weather/2x/drizzle_light_color_96dp.png

http://www.gstatic.com/images/icons/material/apps/weather/2x/showers_rain_light_color_96dp.png

http://www.gstatic.com/images/icons/material/apps/weather/2x/heavy_rain_light_color_96dp.png

http://www.gstatic.com/images/icons/material/apps/weather/2x/strong_tstorms_light_color_96dp.png

http://www.gstatic.com/images/icons/material/apps/weather/2x/isolated_scattered_tstorms_day_light_color_96dp.png

http://www.gstatic.com/images/icons/material/apps/weather/2x/isolated_scattered_tstorms_night_light_color_96dp.png

http://www.gstatic.com/images/icons/material/apps/weather/2x/scattered_showers_day_light_color_96dp.png

http://www.gstatic.com/images/icons/material/apps/weather/2x/scattered_showers_night_light_color_96dp.png

http://www.gstatic.com/images/icons/material/apps/weather/2x/partly_cloudy_light_color_96dp.png

http://www.gstatic.com/images/icons/material/apps/weather/2x/partly_cloudy_night_light_color_96dp.png

http://www.gstatic.com/images/icons/material/apps/weather/2x/mostly_sunny_light_color_96dp.png

http://www.gstatic.com/images/icons/material/apps/weather/2x/mostly_clear_night_light_color_96dp.png

http://www.gstatic.com/images/icons/material/apps/weather/2x/mostly_cloudy_day_light_color_96dp.png

http://www.gstatic.com/images/icons/material/apps/weather/2x/mostly_cloudy_night_light_color_96dp.png

http://www.gstatic.com/images/icons/material/apps/weather/2x/sunny_light_color_96dp.png

http://www.gstatic.com/images/icons/material/apps/weather/2x/clear_night_light_color_96dp.png

Where are these images from? Is there a license available?

Can we use these icons in our app/site? Is there a license?

@JordyEGNL No, you can't it protected under Google licencing.

Can we use these icons in our app/site? Is there a license?

@JordyEGNL

If you want icons , check out Openweathermap API
https://openweathermap.org/weather-conditions#How-to-get-icon-URL