Cyclone Herwart was a

European windstorm European windstorms are powerful extratropical cyclones which form as cyclone, cyclonic windstorms associated with areas of low atmospheric pressure. They can occur throughout the year, but are most frequent between October and March, with peak ...

that affected Southern

Denmark Denmark is a Nordic countries, Nordic country in Northern Europe. It is the metropole and most populous constituent of the Kingdom of Denmark,, . also known as the Danish Realm, a constitutionally unitary state that includes the Autonomous a ...

Germany Germany, officially the Federal Republic of Germany, is a country in Central Europe. It lies between the Baltic Sea and the North Sea to the north and the Alps to the south. Its sixteen States of Germany, constituent states have a total popu ...

Poland Poland, officially the Republic of Poland, is a country in Central Europe. It extends from the Baltic Sea in the north to the Sudetes and Carpathian Mountains in the south, bordered by Lithuania and Russia to the northeast, Belarus and Ukrai ...

Austria Austria, formally the Republic of Austria, is a landlocked country in Central Europe, lying in the Eastern Alps. It is a federation of nine Federal states of Austria, states, of which the capital Vienna is the List of largest cities in Aust ...

Hungary Hungary is a landlocked country in Central Europe. Spanning much of the Pannonian Basin, Carpathian Basin, it is bordered by Slovakia to the north, Ukraine to the northeast, Romania to the east and southeast, Serbia to the south, Croatia and ...

and the

Czech Republic The Czech Republic, also known as Czechia, and historically known as Bohemia, is a landlocked country in Central Europe. The country is bordered by Austria to the south, Germany to the west, Poland to the northeast, and Slovakia to the south ...

on 28–29 October 2017. Named by the

Free University of Berlin The Free University of Berlin (, often abbreviated as FU Berlin or simply FU) is a public university, public research university in Berlin, Germany. It was founded in West Berlin in 1948 with American support during the early Cold War period a ...

Meteorology Department, the storm was an

extratropical cyclone Extratropical cyclones, sometimes called mid-latitude cyclones or wave cyclones, are low-pressure areas which, along with the anticyclones of high-pressure areas, drive the weather over much of the Earth. Extratropical cyclones are capable of p ...

formed as a secondary low to a more northerly centre of low pressure named ''Grischa'' coming southward from the Svalbard Islands region, the latter splitting in two low-pressure areas late on 28 October. The center of Herwart started rotating counterclockwise around the main low pressure area, passing over

Norway Norway, officially the Kingdom of Norway, is a Nordic countries, Nordic country located on the Scandinavian Peninsula in Northern Europe. The remote Arctic island of Jan Mayen and the archipelago of Svalbard also form part of the Kingdom of ...

Sweden Sweden, formally the Kingdom of Sweden, is a Nordic countries, Nordic country located on the Scandinavian Peninsula in Northern Europe. It borders Norway to the west and north, and Finland to the east. At , Sweden is the largest Nordic count ...

Latvia Latvia, officially the Republic of Latvia, is a country in the Baltic region of Northern Europe. It is one of the three Baltic states, along with Estonia to the north and Lithuania to the south. It borders Russia to the east and Belarus to t ...

and then losing power while moving over western

Russia Russia, or the Russian Federation, is a country spanning Eastern Europe and North Asia. It is the list of countries and dependencies by area, largest country in the world, and extends across Time in Russia, eleven time zones, sharing Borders ...

. In Denmark, which was hit on 28 October, the storm was named ''Ingolf''. In Hungary, the storm was named ''Nárcisz'' (''Narcissus''), a Hungarian female name whose

name day In Christianity, a name day is a tradition in many countries of Europe and the Americas, as well as Christian communities elsewhere. It consists of celebrating a day of the year that is associated with one's baptismal name, which is normatively t ...

is on 29 October.

Meteorological history

Impact

The storm and rainfall caused death and destruction. Train connections were closed in Northern Germany, and major bridges in Denmark were closed for traffic. Herwart caused disruption to the German energy market as the strong winds caused an over-supply of energy onto the German power grid. Prices for energy slipped into negative values as low as minus €83.06 per megawatt hour, with an average low of minus €52.11 (normal energy prices are €37 per megawatt hour). These values were the lowest since Christmas 2012. This can lead to a situation where Austria and Switzerland find it attractive to use the energy in their pumped storage reservoirs, where it can later be sold back to Germany. Herwart was not as strong as Xavier which struck Germany earlier in October 2017. Herwart is considered one of the strongest storms of the past 10 years in Germany, ranked in 8th place in the strongest storms there in the last decade, but not considered memorable when compared to the strongest storms such as Kyrill (2007) and

Lothar Lothar or Lothair is a Danish, Finnish, German, Norwegian, and Swedish masculine given name, while Lotár is a Hungarian masculine given name. Both names are modern forms of the Germanic Chlothar (which is a blended form of ''Hlūdaz'', me ...

(1999). Herwart was responsible for the worst insurance losses in the Czech Republic since the storms Kyrill and Emma (2008).

References

External links

* Herwart 2017 in Denmark 2017 in Germany 2017 in the Czech Republic 2017 in Poland 2017 natural disasters Natural disasters in Denmark 2010s disasters in Denmark {{Natural-disaster-stub