UK Storm and other bits

Today's storm has been interesting so far, but not for the reasons I was expecting. For one thing, so far, at my location, it hasn't been quite so bad as I thought it might be. We've had worse winds recently (especially the storm a couple of days after the Lincolnshire earthquake) and, so far, it's nowhere near as bad as the January 2007 storm. The main reason why it's interesting is how low the pressure is at the moment.

As my weather station got up and running I noticed that, on and off, I'd get pressure spikes and dips – these would last for one reading, rarely two, and would throw out my graphs and stats. Because of this I added a little bit of "filtering" for the graphs and other things so they'd ignore values that seemed too hight or too low.

For no specific reason I'd set the low point of the filter to 970 hPa. When I got up this morning the pressure reading was already below that and still falling. Because of this I had to make changes to the code that creates my graphs, and also to the code that adds the data to my SQL database, so that the low point is 960 hPa. The pressure is still falling and I suspect I might need to change this again so that the low point is 950 hPa (this would result in a range of 950 hPa to 1050 hPa, which would actually fit rather well with the usual range mentioned on this Met Office page).

Edit: (2008-03-10 13:00 UT) Sure enough, I've just had to modify the minimum pressure filtering again to take it down to 950 hPa because the pressure has just fallen below 960 hPa.

In other recent news (I've not really written much on this blog recently, sorry about that) I've had a couple more base station crashes. The first was on 2008-02-28 and I lost about ½ an hour's worth of data. The second was on 2008-03-08. This is the first time in quite a long time that I've had two crashes so close to each other.

One year of data

It's now 1 year since I first got open3600 running on my GNU/Linux box and got it talking to be WS3600. The first data recorded was at 2005-12-27 14:16 UT, it stuttered a little for a few minutes as I modified a couple of things and then was up and running.

That same afternoon I also started work on the main site.

Some more work on the graphs

Back in July I added some graphs that showed the last 150 days' worth of data. I wrote the code to generate them rather quickly and have not touched it since.

This evening I've made some changes to how they're generated (got rid of the user of gnuplot's smooth facility and have also added some labels) and I've also added two extra graphs: the wind chill and also the impact of wind chill (the latter being the temperature minus the wind chill).

One Year

I've just realised that I've now had the weather station up and running for just over a year. I first installed it on the 17^th of December last year (and wrote about the installation in some more detail a couple of days later).

I don't quite have a year's worth of data collected yet, I didn't start collecting and keeping data until the 27^th of December (that was the same day that I started work on the main site).

Wind distribution compass

The stats page on my weather station site has always had an all-time wind distribution table. The idea is to get some sort of idea of where the wind generally blows from at my location. While it does give that information it doesn't really have that "at a glance" feel to it that you really want.

This morning I decided that this data might also work well as a "compass graph":

I think that does a very good job of giving a "at a glance" appreciation of the data. What's really interesting is that the two main peaks are west and south-south-west. Generally the prevailing winds in this part of the UK are from the south-west so you'd expect the peak to be there. I suspect that the reason for the result you see above is that there's a house to the south-west of my setup and it's creating a wind shadow.

Giving a little back

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).