30-40 degrees? I guess I'd put on some light tights and a top compression layer and lose the half-finger gloves for some light full-finger gloves. In fact it's been 38*F on my ride in for the last few days, and that's what I've been wearing. I still sweat just a bit but it's pretty comfortable.
The coldest I've ridden is -25*F, on 2 days, and < -15*F for a handful of days in the last few years. The cold really doesn't bother me (I just layer up, switch to thinsulate lined hunting boots and gloves and a neoprene balaclava), what bothers me is when there's heavy, wet snow; studded tires are fine for ice but wallow around a lot if I get on streets with 8 inches of unplowed snow.
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Work: the 8 hours that separates bike rides.