I love the rain…
Want a nice and mac-friendly software that talks to your sassy weather station? Forget about it, such a thing doesn’t exist yet. Well, there is Weather Display, a solution developed by enthusiasts, but it’s a difficult to install port from Linux and quite pricey. A free Linux command line utility that logs to a database exists but it has some problems and I couldn’t get it to run stable enough.
I’m very fond of the weather stations WMR100N and WMRS200 from Oregon Scientific which have good price-performance ratio, and wanted a simple plug-and-play logger running natively on my mac. Since there wasn’t any that google could find, I have begun writing it myself. Based on some reverse engineering efforts done by brave people around the net, and my own urge to become a better Cocoa programmer, I have put together something that works very well for me. And I will be sharing with whoever wants it. There’s some more work to do before it’s reasonably rich on features and I can release a 1.0 version. But come back soon, things change rapidly.
The current version works and is running stable in my summer house. It logs every other minute to a CouchDB instance and also tweets every hour. There is no graphical user interface, except a preference pane to handle settings, but that will come later.
A note on Oregon Scientific: I have mailed and called them several times and asked about their interest in getting a mac client for their weather stations, and about possibility to access the protocol for data encoding and USB communication. But the only answers I’ve got so far is “you can run our software in a PC” and “the protocol is not public” and “no we haven’t received any mails from you… oh, that mail? I remember now but can’t find it. Can you send it again?”. So I guess they either are completely uninterested in opening up for the mac market, or that external developers are bad bad bad and dangerous to even talk to. Thank’s for nothing, Oregon Scientific. I’m now rebelling with reverse engineering.
It tweets!
Decoding data
Since Oregon Scientific has decided to ignore all requests decoding is done by reverse engineering. If you have more info, please contribute. Mail me at per@ejeklint.se.
USB Protocol described (Work in progress)
Installer
A ready-to-use installer package will be available in the future, but for now you must grab the source and build it for yourself. You need at least Mac OS X 10.5 and XCode installed.
Source code
Source is GitHub, free for all. Beware that it’s still in early stages. But I’m slowly learning. 
If you have any contributions, you’re more than welcome.
FYI, the GitHub link generates an “Access Denied.”
Probably just a temporary glitch, just checked and it works fine for me.
http://www.tee-boy.com/WeatherSnoop.html
Weather Display works great using WeatherSnoop to grab the data from the WMR100.
Hi, I also want to purchase a WMR100N for my home in french brittany in loctudy. I’ve set up a soekris with a webcam and a very elementary weather station. The soekris runs openbsd (could be linux). You have made quite a good job to reverse engineer the data with the macosx program, well done. How difficult would it be to catch the data (using python or c), and then use rrdtools to create related images (that what I do on http://www.loctudy.com, it’s only functional and has to be designed to become acceptable). Any help should be extremely appreciated. Jean-François
Hi Jean-François! I’m planning to support rrdtool in the future, but that’s months away since I have very little time for hobby projects right now. If you want to run on Linux I recommend the free consolewd from here. It works and people have used it together with rrdtool. There are some threads about it and rrdtool in this forum as well. Hope this helps!