Storm Poly – Strongest summer storm on record hits the Netherlands

An exceptional summer storm named Poly by the German Weather Service wreaked havoc in the Netherlands on July 5, 2023. Recognized as the strongest summer storm ever and the overall strongest since January 2018, Poly brought record-breaking wind speeds to the country, causing widespread damage and claiming at least one life.

An extraordinarily powerful storm named Poly swept over the Netherlands on July 5, 2023, marking the most powerful summer storm ever recorded in the country and the most potent since January 2018, according to data from Weeronline meteorologists.

Poly’s intensity was underlined by a wind gust recorded in IJmuiden, hitting 146 km/h (90.7 mph), marking the strongest summer wind gust ever recorded in the Netherlands. This unprecedented event led to the issuance of a Code Red weather alarm in the provinces of Noord-Holland, Flevoland, and Friesland due to very strong wind gusts. The National Meteorology Institute urged people not to leave their homes and to reserve emergency service numbers for life-threatening situations only.

The Haarlem area was particularly hard-hit, with numerous reports of trees collapsing on homes and cars. Tragically, there was one fatality in Haarlem when a falling tree struck a car.

In Amsterdam, storm damages were extensive, and two individuals sustained serious injuries. In response to the harsh conditions, Amsterdam’s Schiphol airport, one of Europe’s busiest hubs, canceled over 400 flights. A spokesperson indicated traffic would be limited until at least 16:00 local time on July 4. Train operators NS and Arriva suspended all services in the country’s north, and a major highway north of Amsterdam was closed due to falling trees.

Rainfall was heaviest in the center and west of the country, with widespread measurements of 20 to 30 mm (0.8 – 1.2 inches). In localized areas, rainfall exceeded 40 mm (1.6 inches).

The intensity of the storm weakened in the Netherlands by the afternoon as its center continued its journey NNE over neighboring countries.

While strong storms in the Netherlands usually occur between October and April, Poly has redefined this norm. The previous severe storm that hit the country was on January 18, 2018, while less intense ones than Poly also hit the country during the summer months — on July 25, 2015, and August 26, 2020. Weeronline reports that the 2015 storm, the previous summer record-holder, produced wind gusts peaking at 122 km/h (75.8 mph), also measured in IJmuiden.

References:

¹ Live-blog teruglezen: zeer zware storm Poly trok over ons land – Weeronline – July 4/5, 2023

² One dead as rare summer storm hits Netherlands – Reuters – July 5, 2023

Featured image: Storm Poly at 04:30 UTC on July 5, 2023. Image credit: EUMETSAT/Meteosat-10, Zoom Earth, The Watchers