Currently reading a book about ferry pilot adventures. One technique used when ferrying, when loaded up with ice, was to fly so close the water the salt spray from waves would wash over and deice you.
Since you're not navigating the North Atlantic, I wouldn't fly.
Seriously though, I wouldn't unless you can pick a safe altitude at least couple degrees above freezing. Even then, always have an out incase something unforeseen happens...higher, lower or laterally. Your flight planning should have a healthy dose of airmass study and temperatures aloft along your route of flight.
Here's what I know about icing...
- Visible moisture must be present
- The temperature of the collecting surface must be at or below freezing, the OATs only relevance is that it effects the temperature of said surface