posted September 05 2013
on Erik Romijn

WeerAPI: a ridiculously simple weather API

This week I was talking about open data at the Netherlands Environmental Assessment Agency, together with several others from the Appsterdam community. In the process, I found myself needing some realtime very basic weather data: what is the current wind direction in the Netherlands, and what is the current wind speed?

This data is collected and published by the KNMI for 36 places in the Netherlands. However, to my surprise, there is no structured format available. All they have is an HTML table. So despite thousands of open datasets having been published in the Netherlands, there is no structured way to find the current temperature on Texel.

I found this so incredibly ridiculous, that I went ahead and built it myself: the WeerAPI. It scrapes the KNMI website and has a single call for now, for the current conditions at 36 measuring stations. I enrich the data with the wind direction in degrees, wind speed in Beaufort and a very rough geographical location of the measurement stations. It’s free to use and open source, but you’ll have to credit the KNMI if you use the data. Updates come in every 10 minutes.