Sometimes it's a result of thermal activity, bubbles of warmed, moist air
rising from plowed fields, parking lots and so forth.

"Jay Honeck" wrote in message
ps.com...
I'm always surprised by the development of puffies in a row --
especially a sharply defined, very small row. It's hard to imagine
what is happening in the atmosphere to cause their development in such
a tighly defined area, but I see them fairly regularly around here.