According to the KNMI, The Royal Netherlands Meteorological Institute, in the future the Netherlands can expect more frequent severe storms such as those experienced at the start of this week.

Bart van den Hurk, a climate researcher at the KNMI, states that the Netherlands’ climate is changing, resulting in not only rising temperatures but also more extreme rainfall, in winter and especially in summer.

On Monday, the violent thunderstorms and heavy precipitation were so extreme that the KNMI released a "code orange" warning. In some places more than 100 mm of rain fell within two days.

Warmer summers with intense rainfall

Van den Hurk states that the recent storms are part of a clear pattern showing an increase in the occurance of extreme rainfall.

In May, the KNMI published a report on climate scenarios for the Netherlands up until 2085. The report highlighted two constants: a rise in temperatures, and the increase in extreme rainfall.

Despite predictions that summers will be warmer and drier, it is also predicted that more water than ever will fall in the Netherlands, due to increased amounts of water vapour in the atmosphere.

Wettest day on record?

The storms on Monday led to speculation about whether the Netherlands had just experienced its wettest day on record.

Weatherman Mark Putto attempted to claim the record by tweeting that never before had more than 100mm of precipitation fallen on so many council districts across the Netherlands. Meteorological institutions dismissed his claim, stating the data was not comparable.

According to weeronline.nl the current top three records for rainfall in 24 hours are:
› Voorhuizen, 3 August 1948: 208 mm
› Amsterdam, 9 August 1951: 148 mm
› Gouda, 24 June 1975: 146 mm

Recovery rates after storms

Some areas, such as Amsterdam, saw sudden local flooding that covered roads, filled basements and sewers, and interrupted tram traffic.

However Waternet reported on Tuesday that, since precipitation was not ongoing, water levels were already returning to normal.

In other areas, such as Maarssenbroek near Utrecht, water authorities were still operating emergency pumps late on Tuesday to prevent polders along the A2 highway from overflowing.

10 million euros damage

The Dutch Insurers Association (Verbond van Verzekeraars) is estimating initial damage costs to homes at 10 million euros. They expect this amount will further increase when claims for cars and agriculture are also taken into account.

Canal crayfish emerge

The heavy rainfall generated one unexpected outcome: the emergence of many crayfish from Amsterdam canals. Social media users posted about the surprise appearance of young lobsters next to canals. The creatures chose rainy periods to explore their surroundings to avoid drying out.

Crayfish are not native to the area but appeared around 20 years ago. They are considered pests by the water authority, with numbers estimated to be at least several hundred thousand in the Amsterdam area, according to Waternet ecologist Bart Specken.

Sources: Volkskrant, KNMI