<sigh> I feel your pain. There's a reason I know that (VERY LARGE VERY LOUD) Great Pyrenees will happily warn off coyotes ALL NIGHT. The sheep-guarding breeds will sometimes just do that, which is why PEOPLE WHO LIVE IN RESIDENTIAL AREAS SHOULDN'T KEEP WORKING BREEDS AS DECORATIVE PETS DAMMIT whoops sorry I digress..

but anyway, the below-20 isn't going to ring any alarm bells on its own. Plenty of dogs can be just fine down into the single digits if they have a dry spot and wind protection.

You're probably going to have to do this from the reasonable-expectation-of-peaceful-enjoyment angle.

If you own your home, the town needs to help you out as a taxpayer. If you rent, is your landlord on board with going to bat for you? Landlords don't like to lose money/good tenants over this stuff, and you're back to the taxpayer thing again.