I've always thought it silly to make the decision too early, forecasts are often wrong, this morning was supposed to be 300m vis & broken at 300ft until 12 before "becoming 10km vis & SCT 3500" yet today turned out to be very pleasant from about 9am where I am. Always err on the side of caution, but you could always re-assess early morning.
If you don't like it - drive there rather than to the airfield! :-)