Been a while since a view from my window, so when this cloud/light combo drifted past I thought it might do.
The halos I'm talking about are those that appear when you mess with shadows too much (or HDR type plug-ins), often along horizons. You can easily see this on the right and on the left an effort to get rid of it. In most circumstances it's easily done using the healing brush set to "darken" in the blend mode. If this is ever a problem for you, try it - it's easy.