The heat was driven out last night by rain and thunder. The weather change also caused a special line of lines in the air above Drenthe. Various fellow students sent photos of the phenomenon, asking: what exactly is this?
RTV Drenthe weatherman Hans Nienhuis has the answer: “It’s a so-called shelfcloud. The cloud is a normal phenomenon in thunderstorms. Such a cloud lives on moist warm air that is pulled into the shower and rises at great speed to 10 kilometers. Deep in the cloud, the process with precipitation starts. “
Where the warm air goes up, cooled air must also be lowered again. “It falls back to the ground in the middle of the shower and there it spreads under the cloud in a growing pool of cold, wet air. Those are the rains and gusts of wind that we have at a shower,” Nienhuis explains.
The layers that can be seen on the photos are subtle differences in the humidity of the air that is sucked inwards. “So that it sometimes condenses a little earlier or a little later.”
According to Nienhuis, a shelfcloud Not dangerous. “But it does mark the place where you end up in the cold air from the warm damp air. You often see gusts of wind at that location. And a few minutes later it will also rain.”
A literal translation of a shelfcloud is a shelf cloud. But you don’t hear that word back often. Nienhuis: “It is not really a nice translation in Dutch. Sometimes you read Buienkraag, but that is also not general.”