Rare, potent summer windstorm turns deadly in Netherlands and Germany

A powerful storm with fierce winds and heavy rain slammed the Netherlands and northwestern Germany Wednesday, leaving at least two people dead, The Associated Press reported.

Photos and traffic cameras showed trees toppled over onto sidewalks and cars in Amsterdam as well as on motorways throughout the northern portion of the country. The Royal Netherlands Meteorological Institute said this was the worst windstorm to strike the country in the month of July and one of the most powerful summer storms to affect the country in more than 50 years.

One woman was killed in the Dutch city of Haarlem when a tree fell onto a car. Elsewhere, a man was killed by a falling tree in the northwestern German town of Rhede, the AP reported.

The windstorm, which was named Poly by Germany's weather service, is considered to be quite rare for this time of year. Windstorms as powerful as these are more often seen during the late autumn to early springtime period in this part of Europe, according to AccuWeather Senior Meteorologist Tyler Roys.

The Dutch weather service said that a 90-mph wind gust was recorded in the port city of IJmuiden. The meteorological institute issued a code red, its highest warning level, for the provinces of North Holland, Flevoland, Friesland and the IJsselmeer area. Code orange and yellow warnings were in effect for other parts of the country. Poly's arrival marked the first time that a code red warning had been issued in the country since Storm Eunice swept through the region in February 2022.

Rail service was severely impacted across the northern parts of the country, and hundreds of flights were canceled at Amsterdam's airport. The AP reported that parks were closed in Amsterdam and people in North Holland, where Amsterdam is located, were urged to stay indoors.

In Germany, a Level 3 red warning was in effect for northern parts of the country, including Hamburg, on Wednesday. A Level 3 warning is the second-highest warning on the country's four-tiered weather alerts system.

Storm Poly is seen on a visible satellite image on the afternoon of July 5, 2023. (NASA)

Roys said that the storm rapidly developed as it moved across the English Channel on Tuesday and into Tuesday night. Wind gusts ranging from 50-60 mph occurred across northern parts of the Netherlands and far northwestern Germany.

"What increased the damage from this storm was the fact that the trees have all their leaves," Roys said. "When you introduce wind gusts above 50 mph, the likelihood for branches to break off increases, especially when you have gusts of 70-90 mph, which occurred in a narrow corridor from Ijmiuiden to Amsterdam to Hourtibdijk."

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