Aren't (some of???) the Davis Instruments weather stations 1-wire systems?
I've never been able to find proof of that online. Maybe I've just been wording my queries wrong, but I've been very surprised not to find any internals info on them. But their use of telephone-style wiring suggests it.
But, even if they aren't, you could use the mechanics from one as a base for a 1-wire anemometer.
Another possibility would be to put something like an ATTiny in the anemometer, and send the data using RS-422. I'm thinking (perhaps erroneously) that pretty much all the noise from the radio station would wind up being common-mode, so the data would get through reliably.