The wind tunnel calibration data for the anemometer goes up to 60, but Ron has customers who have used the anemometer on a storm chasing vehicle going 70mph into a 50mph headwind. So, the thing is tough. I've personally measured gusts over 60mph and I'm sure I'll see higher as the spring unfolds.
Other Options for Buying the Sensors
There's a sister site to Fascinating Electronics, WindDataLogger/APRS World, which also provides the same sensor setup preassembled, so if you aren't interested so much in the mechanics and want to accelerate that part of the project, you can buy an assembled version of this from WindDataLogger.com. The assembled version of each sensor is about $20 more than the kit version. So, for both sensors you'd pay about $40 more than buying it in a kit.
The folks at WindDataLogger/APRSWorld estimate the wind vane kit takes an hour and the anemometer less than an hour. This is if you buy their kit. If you buy the Bag-O-parts version like I did from Fascinating Electronics, there's more to do in that kit. For example, the ball-bearing in the anemometer is not pre-installed, but in the WindDataLogger/APRSWorld kit, it is. Saves time and setup to epoxy the ball-bearing. Another example is the kit from Fascinating Electronics didn't include any wiring or RJ45 jacks at the sensor end, but the kits from APRS World do. This is a big time savings since you won't have to spend any effort deciding on wiring solutions and connections.
This is a shot of
the partially assembled anemometer kit from APRSWorld which
solves the wiring/connector problems if you'd rather not do
If you build the sensor kit from Fascinating Electronics as I did, you should plan several evenings to get it put together and plan to rig your own wiring. Unless you're interested in the mechanics, it's well worth spending the extra $40 for the fully assembled version of the sensors from APRSWorld.
To summarize, there are different levels of difficulty you can choose to get into the sensors. You can buy the scratch kit from Fascinating Electronics, buy the partially assembled kit from APRSWorld, or the fully assembled modules from APRSWorld.
Also, if you don't want to build your own OSCirrus electronics but like the idea of this type of project, you can also buy off-the-shelf wind data loggers from the same site. OSCirrus is definitely geared toward a Do-It-Yourself software developer who would like to learn more about hardware.