Breaking through the haar

The word "haar" was one of the first Scottish words I learned when I moved to Edinburgh. It always seemed to me that "haar" better described this weather phenomenon moving in from the North Sea better than "fog". Like many Scottish words (such as dreich and swither) they seem to be more descriptive than the standard English word or phrase. According to good old wikipedia "haar" could derive from Low German/Middle Dutch hare or perhaps Saxon. Apparently in Yorkshire and Northumberland it is referred to as "sea fret". If any of you blippers have any further insight into the derivation of the word "haar" drop me a line!