Yep Leon, it was certainly a wierd night. I too was all set-up after a glorious day. The weather report was for clear sky all night. The night came with crystal clear sky, no wind, cool temp, and I started imaging around 10:30pm. About half an hour later nothing was showing up on the imaging or guiding monitors.
Poked my head outside and yep . . Solid cloud. It stayed all night.
This morning was clear as a bell again
I'll see what happens tonight. So far so good . . . again.