Differences between Love nips and biting... Also, fear of rain.

Question
I have a 9 week old Pitt Bull/German Shepard mix puppy, and after 3 days with my boyfriend and I, she is surprisingly well behaved and house-broken.... Except when it rains. She already knows to go to the door when she wants outside, and will lick my face and whine to wake me up to go out in the mornings. But, when it rains, she refuses to go out, giving us no signs until its too late, and only wants in when pick her up and put her there. How can we get her over her fear of the rain? We thought maybe just gettig her used to water in general?  And as a puppy, of course she likes to chew, and I sort of understand the concept of "love nips" when shes nestled into my neck or shoulder. Shell start to lick me, and will "gently" or as much so as she can be, nibble my ear or face. As cute as it is, she already has very strong jaws, and it hurts. Pitts particularly are deemed as aggressive breeds, but I know from owning one previously that they are not. Its all in how they are raised. But we got our full-blooded Pitt after her puppy stage. When we play, and she uses a lot of teeth, ive noticed holding the scruff of her neck will sort of immobilize her. Will this work, if followed by a firm "no"?
Please give me your opinion... I love this little girl, and cant imagine someone telling me I have to put her down for biting anyone, so I want to give her the best trainig and happiest home possible.

Answer
Hi Tiffany.  The next time you have rain, take her out on leash into the yard and take your very best treats with you - for example:  cheese, hot dog bits, leftover meat cut into pieces no bigger than a pea.  Have a party in the grass, asking her to find the treats in the yard.  Reward her for walking in the grass by feeding a tidbit every couple of steps.  Don't allow her to have accidents in the house.  Use a crate or exercise pen for confinement.  Take her out every 20 minutes when she's awake or after a play session or anytime you see her sniffing around.  You MUST go out with her, though.  Don't assume she's eliminated if you didn't see it happen.

Regarding the second issue - don't allow a dog that's going to grow up to be at least 60 pounds nestle in your shoulder or neck.  She needs to learn now that she gets no attention unless all 4 paws are on the floor.  Sit on the floor and play with her, but don't allow her to climb on you.  Interrupt the licking before it becomes biting.  Puppies have to chew on something, so you should always have an acceptable chew toy or bone within reach whenever she gets into a nibbling mood.  Using forceful, physical methods (like a scruff grab) to get a pit to stop mouthing or biting isn't necessarily the best way to deal with it.  It might even cause the dog to escalate.  If necessary, get up and walk away if she insists on using your hands or arms as chew toys.  She'll soon learn that using her mouth inappropriately causes her favorite playmate to go away.  

Please let me know if you have further comments or questions or need clarification on anything I've recommended.