Seeing conditions over water have been discussed here, but I have not come across the the temperature factor between water and air.
I live on Puget Sound north of Seattle. A fairly deep seven mile inlet is at the edge of my property about 200 feet away. I am about 100 feet up above the water. When the water temp is warmer than the surrounding air the seeing is absolutely horrible! Its not the buzzy fuzzy of the jet stream, but slow deep waves. It took me awhile to discover the pattern, but I finally realized it was due to heat plumes coming off the water.
It may seem obvious, but the local water temp is always between 45-50F. Not exactly warm, but when the air is in the 20s or 30sF the heat rises like over a road in a summer desert. It strange to think of such profound heat waves generated by 45F degrees. Good news is once the air temp rises above the water the heat tends to sink and the waves go away.
Obviously our local jet stream can obliterate good seeing, but for those of you looking out over any type of water, especially water that does not freeze, its something to consider.The seeing with these heat plumes is much much worse that even the worst jet stream nights and if you are close enough to the water, like me, the corrupted seeing can radiate in every direction of the sky.
Good news is this corruption goes away when it gets a bit warmer, for me anything above 45F in the winter and 50F in the summer.
Edited by Maxtrixbass, 19 February 2025 - 02:06 PM.