Put new front brake rotors/pad on yesterday and was planning on bedding them in by doing about 8-10 hard stops from 60 mph to 10 or 15 mph, and then driving on freeway for a bit so they can cool, but its raining.

Not a very hard rain, more of a sprinkle. Aside from the risk of driving in the rain, can I bed in brakes while it is raining? Will the water prohibit proper wear on the new rotors and pads? And will the water affect the caliper grease (brake quiet spray)?

 

It's possible, though I'd be extra careful not to splash in any puddles. It doesn't seem like a good idea to get your pads/rotors nice and hot just to splash (and cool) part of them with some water.

My favorite method to bed brakes is to go someplace where I can drive at speed and just drag the brakes with my left foot while maintaining speed. It's worked out well for me so far, with the added benefit of not having to worry about that complete stop bit. I imagine, using this method, it would probably be a lot easier to get heat into the pads/rotors in the rain.

 

Just drive carefully until it is dry. You can bed them in a couple of days when it is dry.