I've added a tools section to my weather station website. The idea is to make available some of the tools I've written that make the station work (at least those that have a chance of being useful to other people — a lot of the code I've written is very specific to my setup and it wouldn't make sense to publish it).
Yet more messing about with the wind compass graph. After having it up and running for a few days I started wondering what it might look like if I created a video of the graph building up over time. This is the result:
The data is taken from 2006-11-26 and covers the first couple of hours of the day.
After adding a wind compass graph to my site's graphs, and then after improving them (with a bit of help from Tim), Tim's gone and nicked the idea for his own graphs.
Not only that, he's gone and added lots of cardioid graphs too. I'm not sure what they tell me, but they look kind of fun.
After adding the wind compass graphs earlier today I started thinking again about the problem of averaging the wind direction. Being able to produce a useful rolling average helps with the turbulence problem I get with high wind speeds and the compass plots had a minor bug in them when the wind was moving either side of north.
So, after a little bit of searching around on the net and not coming up with anything that useful (maths really isn't my thing so I find it quite hard to make sense of most materials), I hassled Tim and he came up with a couple of useful pointers.
A little bit of hacking on rollavg later and, I think, it's all working. I can now do rolling averages on wind directions and it doesn't seem to all fall apart when the wind is coming from somewhere up north (yes Tim, the pun was too good to miss ;)).
I've now tweaked the compass plots to show both 20min and 60min rolling average values and I've also reintroduced the rolling average lines back into the old wind direction graphs.
Hopefully, this time around, it'll all work sweet.
This morning I added a new type of graph to the graphs for today and yesterday. It's somewhat similar to the wind direction graph but, instead of showing the direction left to right, it plots it as a compass.
Edit: I've now added a compass graph for the last 7 days too.
I also had a bit of a record this morning. At 05:02 I recorded the lowest relative pressure value I've seen since I started running the station. The value was 972.4 hPa, just lower that the last record of 976.7 hPa on 2006-02-17 at 03:37.