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If its windy, are seeing conditions poor?
>> yes, the more the wind the worse the seeing. In any more than a light breeze, say 5 knots max, don't bother setting up.
A slight breeze helps keep the dew off; dead calm = dew.
If its been a particularly hot day, does that make for bad seeing?
>> Yes, because objects on the ground exposed to sun have soaked up a lot of heat and will be a source of thermals all night as they cool down.
There is a huge variability in microclimate too, according to exactly whre you are and what soil type surrounds you.
For example a lush well-gardened or farmed area with black soils that have been well watered are terrible for dew - council ovals, for example, and being dark the soil will radiate heat all night and the temperature drop will be relatively large. Setting up a scope in this kind of terrain you will be fighting dew all night (SCT's, refractors and maks) and having problems with cooling your optics down to the air temp.
An area that is typically light, sandy soil or mostly sandstone will not hold water on the surface (and is unlikely to be watered), and being light coloured, does not radiate heat back to space at night so it will not be so cold.
After spending 20 years observing in the Blue Mountains near Mt Banks at 1050 metres all year round, it was always noticeable that in the sandstone territory at night I never saw a frost and dew was not a problem, yet the tar road (black) could have ice on it at night. Similarly Leura oval (looks like a reasonably attractive place to observe) was a lousy place for dew because it had black soil and was amply watered to keep the grass green.
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