Stormchasing, a peculiar hobby

/ June 15, 2015/ Ocean Circulation and Climate

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9 June 2014; After several days of severe weather across Western Europe, our region was affected as well. An impressive line of thunderstorms formed over Northern France and Belgium, which was preceded by these beautiful mammatus clouds all across the sky. Photo: Arjan Van Beelen.

Many weather enthusiasts will be familiar with the following problem: people do not always agree with you on what exactly is to be called ‘nice weather’. When the weather maps predict warm and humid conditions with chances of heavy showers, some of us get excited. And after quite a bit of discussion, analysis of the latest map and organisation of the logistics the decision is finally made: we go out stormchasing!

When I started my master at IMAU several years ago I met some people who shared my passion for severe weather. Occasionally they would go out on a trip to find and document severe convective storms. With a seat available in the car, this was the perfect opportunity for me to join in. June 2013 presented several interesting situations during which we encountered storms with large hailstones, heavy precipitation and many lightning discharges. Although in Western Europe stormchasers have long been regarded as a bunch of fools that go drive around just to get wet, in recent years they have become more appreciated and better organised. A central platform now exists where registered storm spotters can make reports of severe weather, which are then passed on to the proper authorities. Several recent events such as the disaster during Pukkelpop in 2011 have further raised the awareness how important it is to correctly predict severe weather events.

As a meteorologist, for me personally I think it is also important to really experience extraordinary meteorological conditions. Despite the presence of a vast number of weather stations, these data are only to a limited degree available to the general public, in contrast to for instance the USA. The accuracy of warnings for severe weather events such as strong wind gusts, large hailstones, heavy precipitation and lightning thus increases when the reporter has adequate experience in how exactly these phenomena develop and what their impact can be. For instance, a 90 km/h wind gust at the coast in winter is usually harmless while it could easily down a large tree further inland in mid summer. In addition to this, severe weather is truly fascinating and each specific situation teaches us how to better judge and predict such events. And last but not least, a day of stormchasing is a pleasant social event with a lot of chatting, for instance about the nice landscapes surrounding us. To us, stormchasing is then more than just catching a bit of wind and rain every once in a while; it enriches us with amazing experiences and simply makes us better meteorologists.

Michiel Baatsen, PhD student in the Oceans and Climate research group at IMAU

19 June 2013; The setting sun lights up new cells growing at the backside of a large multicell complex near Muenster. The expansive anvil cloud consisting of ice crystals is seen above as it covers a large part of the sky during our way back towards Utrecht. Photo: Michiel Baatsen.

9 June 2014; In the approaching line, a so called bow echo formed and headed straight for us. Luckily we found shelter in time as we were battered by winds of up to 150 km/u and multiple lightning strikes each second. This thunderstorm caused severe damage in a nearby village as well as in a vast swath of Nordrhein-Westfahlen. It only just missed the festival area where Pinkpop was taking place at the time,. Photo: Michiel Baatsen.

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5 May 2015; Following a prolonged period of uninteresting autumn-like weather, this was the first day with some decent warmth that was immediately followed by instability. A day of stormchasing ended with the passage of this thunderstorm preceding a cold front that formed a nice arcus cloud, passing with some severe wind gusts and medium sized hail. Photo: Michiel Baatsen.