That Light-bulb Moment?

It was nippy this morning - which meant pink & blue skies and scraping the car before SWMBO headed out for breakfast.
We then went and I chose new glasses.
By the time we got home the roof of the car was still frozen - apart from this spot. I have no idea why this spot always melts first as I am sure it is further forward than the interior light (but I could be wrong).

I haven't broken the ice on the pond today and the Sparrows are a bit hacked off. They certainly didn't hang about and all I got was a shot of the white bark which has appeared on one of the hedge stems.