Tag: super cell

Devastating Super-Cell Storms August 2023 Over Bavaria

August 2023 saw extreme weather events in Middle Europe. It wasn’t so many events, but a couple of significant storms. A number of super cells in Germany led to damage. There were some typical weather patterns in Upper Bavaria along the alps, where notorious hail-stripes are well-known, but the intensity of extreme weather was surprising.

One of the most significant extreme weather events happend on August 26 in the afternoon. Two supercells brought incredible amounts of hail in Southern Germany. A number of 123 places were affected, according to German Weather Service DVD. The separate weather systems rolling over Bavaria with a distance of 100 km. The two super-cells left a trail of destruction at a length of 130 km. The strip of hail had a width of 15 km. In that zone there was a lot of destruction in Benediktbeuern with a well-know monastery and Bad Bayersoyen. In some places hail had diameters more then 5cm, which turns them into bullets with high speed. Between the strips there was no such destruction but strong gusts of wind. The maps of the Europan Severe Weather Database deliver an impression of the two trails of destruction.

Heavy Thunderstorm on August 13 with intense lightning

Before these events, there were also heavy thunderstorms on August 13. These storms were coming from Baden-Wurttemburg. The video on the stormypictures.de Youtube Channel shows how the storm quickly intensifies. There was also a remarkable amount of lightning. The immense rate of lightning lit the sky and lasted unusually long.

There are no fundamental new weather patterns here, but what happened is what climate-researchers predicted a long time ago. A hotter and wetter atmosphere contains more energy. This energy is a precondition for stronger storms as these super-cells. And it is not only a warmer atmosphere. Early this year, researchers detected unusual warm surface temperatures in the oceans for example the atlantic ocean near Florida.

Here is the development of the thunderstorm in the early evening hours of August 13 in Upper Bavaria, close to lake Ammersee:

The late sun illuminates towering thunderstorm clouds

At first sight the huge tower of clouds looked impressive but not as monstrous it became.

There was an incredible dynamic in the chaotic atmosphere

Within minutes the sky changes and dark clouds approached fast. In the upper half a rotating pattern appeared.

Lighting strikes came close very fast and a huge curtain with fall stripes appeared.

This storm brought intense rain and hail in some places. Later there was intense lightning.

The supercell storms on August 26 seen from a ship on a lake

There had been further dramatic weather events after August 13. On August 17 a monster thunderstorm set parts of Nuremberg in Northern Bavaria under water after a flash flood. The series of severe weather peaked on August 26 with the two super cells in Southern Bavaria and also dangerous thunderstorms in between. The pictures below were taken on a ship on Lake Ammersee. Here it was very hot and the sky was clear til middle of the afternoon. Then, dark clouds were arriving very fast. The orange flashing lights on the storm warning lights were activated. It was important that sailors headed back to harbour in time because the line of thunderstorms arrived fast with strong winds and rainfall later.

An unusual sight

Weather is always unique. Compared to the previous thunderstorms, the sky “looked” more like it was typical rain clouds. However these was a severe weather system at any place. The wind picked up very fast and the normally peaceful lake turned into a raging water with remarkable waves. Strong rainfall let the shore disappear in a sort of mist minutes after the wind gusts appeared. Later the evening, the weather calmed down. However the damage in many regions was dramatic.

Dark clouds approaching from South-West

The clouds quickly become darker.

Still some sunshine in the Alps before the super cell system arrives

It’s getting pretty dark even during the afternoon.

Gusts of storm at the westside of Lake Ammersee in Bavaria. A motor boat makes it barely into the harbour.

What came after the storm

The super cell weather systems were the harbingers of more extreme weather in the alps. The days later there was heavy rain and a flood created more damage in Austria. On August 28 the famous Oetztal was cut off from the outer world after a mudslide destroyed the only road. Many tourists could only leave via the Timmelsjoch mountain pass. Helicopter’s brought food and other stuff into the valley.

Only days later a high pressure system brought calm and unusually warm weather in September. The super cell storms and the following devastating floods were dire reminders what living in a new climate triggered by climate change means. It means coping with a different world, less comfortable, more unpredictable and more violent. August 2023 was also one of the hottest summers on record.

by Waldmeister Categories: UncategorizedTags: , , , , , , ,

Extremwetter mit starken Gewittern in Süddeutschland im Juni 2021

Peter Engelmann,  3 Juli, 2021

2021: Mit einem kalten Frühling blieben die Temperaturen im Mai unter dem Durchschnitt. Zum Glück gab es in vielen Teilen von Deutschland endlich viel Regen nach einer seit 2018 anhaltenden Dürre. Diese hatte in einigen Regionen zu Waldschäden und führte bereits zu Sorgen über die Zukunft des Wasserhaushaltes und der Trinkwasserversorgung. Im Juni folgte eine Hitzewelle. Im Unterschied zu früheren Jahren kam es aber nicht zum Aufbau langanhaltender stationärer Hochdrucksysteme über Europa. Die Wettersituation war nicht über lange Zeit stabil. Die Hitzewelle wurde durch extreme Wetterereignisse beendet. Wieder einmal gab es Situationen, zum Beispiel in Südwestdeutschland (Reutlingen) oder einer Überflutung in Landshut, wie es sie so in der Erinnerung der Menschen noch nie gegeben hat. Darauf folgten viele Diskussionen, ob dies eine Folge des Klimawandels sei oder einfach einzigartige Wetteranomalien.

Nach der Hitze änderte sich in Bayern das Wetter am 20. Juni 2021. Die Tage davor war es überwiegend trocken gewesen mit Ausnahme erster Gewitter im Südwesten Deutschlands und ind den Alpen. Am 20. Juni begann es am Standort am westlichen Ammersee zu grummeln und ein Gewitter mit nur sehr wenigen Blitzen war dort zu sehen. Wie immer gab und gibt es große regionale Unterschiede auf kleinem Raum: Bald gab es starke Gewitterstürme, aber manchmal passierte ein paar Kilometer weiter gar nichts. Das ist nicht ungewöhnlich und bis heute eine Herausforderung für die Wettervorhersage.

Gewitter in den frühen Abendstunden des 20. Junis bei St. Georgen, Diessen, Ammmersee:

Kurzlebige Gewitterzelle am 20. Juni 2021

Die nächsten Tage gab es eine andere Wettersituation: In den späten Nachmittagsstunden oder am Abend kam es zu sehr starken Gewittern. In Süddeutschland wurden auch rotierende Superzellen beobachtet. Noch viel extremere Gewitter gab es in Frankreich, wo eine Luftmassengrenze tagelang für regelrecht katastrophale Zustände sorgte. Die großen Gewittercluster formten sich in Frankreich immer wieder und zogen nach Belgien und Nordwestdeutschland.

Starkes Gewitter am 24. Juni, ca. 18.45 bei Diessen (Ammersee, Oberbayern)

Sich näherndes Gewitter am 24 Juni 2021

Das extreme Wetter mit schweren Gewittern, Sturzfluten, extremen Hagel dauerte in Deutschland mehrere Tage an. Der Grund: Die Luftmassengrenze in Europa verlagerte sich nur sehr langsam. Sie funktionierte wie eine Maschine und erzeugte immer wieder neue Gewitter. Ein Zeitraffervideo vom 21. Juni 2021 gibt eine Idee davon, wie schnell sich oft die Gewitter entwickelten:

Es war interessant zu beobachten, dass ganz unterschiedliche “Typen” von Gewittern auftraten. Am Beobachtungstandort im Südwesten der Ammerseeregion gab es sehr kurzlebige Gewitter, ein Gewitter, das unglaublich schnell aufzog und dann wieder ein Gewitter, das sich nur sehr langsam bewegte. Bei so einem Gewitter konnte man sehr gut Bilder machen. In der Nacht gab es auch etwas, was von manchen als “Stroboskopgewitter” bezeichnet wird. Gewitter, bei denen man gar nicht so viel lauten Donner hört, aber wo es eine unglaublich hohe Rate an Blitzen gibt. Bei den Gewittern gab es auch welche mit sehr starkem Wind aber auch welche, wo kaum ein Wind wehte.

Das Gewitter am 24 Juni erzeugte einige großartige Blitze:

Gewitter am 24. June 2021

Der Gewittersturm unten zog am 28 Juni 2021 auf und war von intensivem Blitzgeschehen begleitet, jedoch völlig anders als das oben erwähnte “Stroboskopgewitter” in der Nacht davor. Die Blitze waren hier viel besser sichtbar. Nach einem der Gewitter gab es auch einen dicken Nebel nach Sonnenuntergang. Später gab es aber am gleichen Abend noch ein Gewitter mit vielen Blitzen. Die stärksten Gewitter kamen dabei meisten aus der Richtung der Alpen.

Gewitter am späteren Abend, 28. Juni 2021, ca. 22.00 Uhr:

Blitze am 28. Juni 2021

Sturzfluten und Superzellen

Schließlich kam es zu einem Austausch der Luftmassen. Die warme, feuchte Luft wurde durch kältere Luft ersetzt. Der 29 Juni war der vorläufige Höhepunkt dieser Gewitterserie in in Deutschland: In Bayern intensivierte sich ein Superzellengewitter, das aus Baden-Württemberg kam und brachte in Landshut in Niederbayern unglaubliche Regenmengen, die die Stadt regelrecht unter Wasser setzten. Die Tage davor kam es zu einem Tornado in der in Tschechien( Czech republic). Das Video unten zeigt die Situation nach dem großen Gewitter am 29. Juni, bei dem es in Oberbayern auch starken Wind gab.

Hier ist ein Punkt, der auch für Photographen und Filter interessant sein kann: Die meisten Leute sind daran interessiert, ein Gewitter aufzunehmen, wenn es heranzieht. Aber es gibt auch noch viele interessante Stimmungen und Momente, wenn das Gewitter durchgezogen ist. Das Video unten zeigt die Atmosphäre nach dem Gewitter am 29. Juni.

by Waldmeister Categories: German Version (Deutsch)Tags: , ,

Extreme Weather In Southern Germany June 2021

Peter Engelmann, July 3, 2021

2021: A cold spring with temperatures in May below average. Luckily there was lot of rain in parts of Germany after a drought since 2018 in some areas which damaged trees and raised serious concerns for example about the future of the water balance and water supply. In June a heat wave followed. However unlike in previous years there were no long lasting high pressure systems. The weather situation wasn’t so far stable for a long time. The heat wave ended with some extreme weather events. And again, we had situations for example in South-West-Germany or in Landshut, lower Bavaria, which were unprecedented. There are a lot of discussions now going on if this is climate-change related or if it is another rare weather pattern.

Things began to change in Bavaria June 20, 2021. The days before had been mostly dry except first thunderstorms in the Southwest and in the Alps. On June 20 there were some rumble and not so intense lightning in the region west of lake Ammersee. As usual there are huge local differences: There were soon stronger thunderstorm whereas a few kilometres apart from that place nothing or little happened. That’s very usual and always challenges weather forecasters.

Thunderstorm in the early evening hours of June 20:

Short lived thunderstorm cell June 20, 2021

The next days there was a much different weather situation: In the late afternoon or evening real strong thunderstorms occurred. Rotating supercell storms were also reported in the Southern Germany. Even more extreme weather happened in France where an air mass boundary created havoc. In France huge clusters of thunderstorms formed repeatedly and moved to Belgium and North-West Germany.

Strong thunderstorm on June 24, 6.45 p.m. near Diessen (Lake Ammersee, Upper Bavaria)

Thunderstorm approaching June 24, 2021

The extreme weather with strong thunderstorms, flash-floods, even extreme hail with enormous hailstones and masses of hail lasted for a couple of days. The reason: The air mass boundary moved only slowly in Europe. It worked like a machine charging up the atmosphere and creating new thunderstorms. A time-lapse video from June 21, 2021 late afternoon gives you some idea how quickly the storms formed:

It was interesting that there were very different types of thunderstorms. The location southwest of the Ammersee experience short-lived thunderstorms, a thunderstorm which arrived very quickly as the next day there was slow movement and plenty of time to take pictures. In the night there was also one of the “stroboscope”-like thunderstorms, where you hear not much loud thunder but you see an incredible light show with high rates of flashes. There were both thunderstorms without wind and thunderstorms with very strong wind.

The thunderstorm on June 24 created some great lightning:

Lightning June 24, 2021

The storm below occurred June 28, 2021 and brought intense lightning. However it was completely different as the “strobe-storm” the night before before. The lightning was also better visible. After one of the storms there was also a thick mist around sunset. Later the mist vanished and another thunderstorm with strong lightning occurred. The stronger storms came mostly from the Alps.

Thunderstorm in the evening of June 28, 10.00 p.m:

Lightning June 28. 2021

Flash Floods and Super Cell Storms

Finally there was an exchange of air mass. The hot humid air was replaced by colder air. June 29 was the climax of the series of thunderstorms in Germany: In Bavaria, a super-cell coming from Baden-Württemberg, intensified and brought an incredibly flash flood in Landshut Lower Bavaria. The days before a deadly tornado happened in the Czech republic. The video shows the aftermath of the big storm on June 29 which was accompanied by very strong winds.

Here is also an interesting thing for photographers and videographers: Usually most people are interested to catch a storm coming to them or before it happens. But there is a lot of possibilities to get interesting moods and pictures when the storm passed. The video belows shows what was going on in the atmosphere after this huge thunderstorm on June 29.

by Waldmeister Categories: Climate Change, Severe Weather, Stormchasing, Summer, Thunderstorm, Uncategorized, Wind, WindstormTags: , ,