One Year of Rain

For the inhabitants of the Netherlands, observing the weather radar, typically with the use of a mobile device, is second nature. And indeed, in a country of above average cycling, and a country of above average rainfall, who wouldn’t want to know what’s in store.

On its website, the Royal Dutch Meteorological Institution has constantly available a gif loop representing the last hour of rainfall, which is refreshed every five minutes. Often, when referring to these images to verify that taking the bike would be safe, or at least would leave me dry, this loop made me wonder what it would look like if this data would extend to covering a whole day, or a week, or even a year.

This curiosity led me to creating a little tool that harvests this data and gathers a day worth of radar images into a 288 frame video file. This tool I created some time ago, using the application Max by Cycling'74. However, I couldn’t start using it as it required a dedicated computer that would be online 24/7, and I didn’t have one available. That changed in the beginning of 2023, when the screen of my laptop went black forever and became available for this task. For various reasons, it still took me a while to set it up.

The storm that was given the name Poly and which hit in July 2023, provided the trigger to finally get to installing the system that would realize the harvesting. Not only rain radar imagery is collected, but wind data as well. Side by side, these images give an impression of how the Netherlands get showered.

Update December 2023

By chance—or were it someone’s prayers?—the year 2023 has been recorded as the wettest in the meteorological history of our little country. And indeed, there has hardly been a day when it didn’t rain. Hurrah! The images collected thus far have been combined in a single video.

This video reveals a lot of interesting features. For instance, showers turning around and returning from where they came from—yes, it is possible to get hit twice by the same rain shower. Or two shower systems, each moving in different directions, that mix and maintain their speed and direction. Also, it appears that rain showers having even a slight eastern direction are extremely rare.