Have you tried giving him treats and rewarding him for going out? You can start out just giving him a treat when he goes potty outside, if that doesn't help he could get a treat for coming outside, then one for going potty.
You could also consider making a covered area for him to go.
My girl's a sissy in the rain too, thankfully she's not a puppy though
Dakota - GSD/Lab Cross - UMJ CGC CA SRD PD MROB1 DAD(Handler/Owner trained)
Alice- APBT mix
Hadhafang vom Adlerhimmel (Natsu)
- WGWL GSD
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