The widget itself is transparent. Accuweather just would need to use a transparent image background.
New LPS bugs: After a device lock brightness is not lowered (i.e. the clock is really bright). It lowers on its own after 5 minutes or so.. If you cover and uncover again the proximity sensor, screen just stays black until I press the power button/unlock. Again, after some time the clock appears at proper brightness level. This is after an OTA update, tried brightness-als and brightness-simple, behaves the same in both.