Thisis a fascinating list:http://en.wikipedia.org/wiki/Sunshower
Its either the devil doing something not nice, or some animal's holiday.
I'm trying to get the phrase "Armadillo's Bar Mitzvah" into currency with little success.
Here in the Northwest, we have a thing called a "Sunbreak". Where in the dark of winter, any peek of the sun is met with a trip outside and a short bask.