Last month, I surveyed a QLCS tornado in southern Germany. It tracked through two villages damaging homes and caused heavy tree damage, with, for example, trunks being considerably thrown.
The tornado originated west of the small village Wackersberg with 67 residents. It went straight through the village, damaging every building within the narrow path (about half of all the buildings in the village). Roofs were damaged and considerable debris impacts were visible in the masonry of residential buildings, e.g. roof parts and tiles that were deeply embedded into walls.
Roof damage is surprisingly minimal for the most part, especially with the residential buildings, as the individual tiles are commonly screwed to the sturdy roof truss, which requires higher wind speeds to lift them. The high stability of roof structure in western Europe also became evident during the IF4 tornado in South Moravia, Czech Republic in 2021, where it was a common picture that the masonry of some (modern) homes was significantly damaged and penetrated by debris, while the roof and especially the roof truss were *relatively* intact (of course, many times more extreme than in this case here). Another reason could be the very fast forward movement of the tornado combined with the small diameter, resulting in a very short impact duration.
Despite the often minor roof damage, there is damage that indicates upper F1 (IF1.5) intensity in the village. For example, a barn that was destroyed, with parts of it being lifted over a hedge and carried for dozens of meters. Metal sheeting was thrown ~ 250 meters.
The tornado then continued snapping several trees east of the village. A steep, forested valley follows. Despite the steep gradient and rapid forward movement, the tornado did not lose contact to the ground and left a continuous path with uprooted/snapped trees and visibly convergent tree fall patterns. Some trees on the left-hand side of the path even fell in the completely opposite direction to the direction of movement. Something that, from what I have observed so far, is rather special in the case of very fast-moving, small-scale events.
In the village of Holnstein at the bottom of the valley, again roofs were slightly damaged, similar to the damage in Wackersberg. The tornado was captured by a CCTV camera here. The video shows the very small vortex (condensed part a maximum of 1-2 meters wide) moving at very high speed. With the footage, I was able to *roughly* calculate the movement speed. It shows the vortex tracking ~ 220 meters in ~ 7 seconds à ~ 31.5 m/s = ~ 113 km/h = ~ 70 mph. Don’t take this result too literally, as it is impossible to calculate perfectly by such footage alone.
Link to the footage:
The subsequent climb on the other side of the valley with a maximum gradient of ~ 50% was probably too much for the tornado. Here a clearly visible trace of the tornado is briefly lost. However, it should be said that the area could not be surveyed in more detail due to the gradient.
South of the village Stauferbuch there was some of the most impressive damage I have ever seen so far. When approaching a visible impacted row of trees, the first thing I noticed were medium-sized branches that stuck deep in the ground dozens of meters west of the tree row. These were therefore thrown in the opposite direction to the movement with visibly a lot of force. In a narrow area of the tree stand, all trees were snapped, uprooted, or at least significantly damaged. Some of which were over a hundred years old. The fall pattern was also extremely convergent.
What was even more remarkable was that the tornado transported tree trunks and many large branches from the tree stand onto the following field. One trunk seemed snapped more than one time. A treetop was transported about 150 meters to the east and then impacted a farm building on the east side, so it must have flown west again for a short time. Small branches were carried up to about 400 meters.
Immediately afterwards, the tornado apparently dissipated abruptly, as no more damage was found. A *possible* explanation for the massive intensity peak just before dissipating could have been the tightening of the ending rotation, as seen often on a larger scale with mesocyclones, whose rotation sometimes becomes tighter towards the end of their existence before disappearing.
The full survey can be found here:
https://www.torkud.de/post/vholnstein24/