It might be worth reaching out to Joel at Open Snow (http://opensnow.com/about/contact http://opensnow.com/about/contact) to see if they'd be willing to share a

It might be worth reaching out to Joel at Open Snow (http://opensnow.com/about/contact http://opensnow.com/about/contact) to see if they'd be willing to share any of their historical weather data (assuming it's what you need, I don't know the ins and outs of weather data other than being an Open Snow user and knowing they have historical records for snowfall for much of the US).