To have our frost as late as October 23rd is unusual. Those tired of cutting grass had to hang in a few weeks longer and gardens gave up bonus produce. I even had tomato plants blooming again after the good rains we had in late September.
It had been cool for a week or more leading up to the frost, but nights were either overcast or windy making a good frost difficult. Saturday night I went out for more logs and the night sky was dense with stars and the air was still. Good night for a frost.
When the sun comes up over the cliff at our house it hits a big lawn bank by the orchard and the frost goes directly from crystals to vapor hurrying back to whence it came. 
The river valley was clear in bright sun early, but quickly developed a dense layer of fog as the same process was happening in all the meadows along the river. An hour later it had all disappeared.
