Catastrophe modeling firm AIR Worldwide has estimated that insured losses from Windstorm Christian (known as St. Jude in the UK) will range between €1.5 billion €2.3 billion [$2 to $3 billion], with the majority of insured losses occurring in Denmark and Germany. Significant insured losses also occurred in the Netherlands, France, UK, and Sweden.

“Windstorm Christian smashed into southern Britain on Monday, October 28, knocking down trees, flooding lowlands, and disrupting travel over land, sea, and air,” said Gerhard Zuba, senior principal scientist at AIR Worldwide. “Gusts of 160 km/h (100 mph) were reported on the Isle of Wight in southern England, and waves greater than 7.5 meters (25 feet) were reported elsewhere along the coast.”

According to AIR, after striking the UK, the storm moved north and east, hitting France, the Netherlands, northern Germany, Denmark, Sweden, and Russia with similar force, and across the Baltic Sea to Latvia and Estonia, where the storm weakened.

The Ile d’Ouessant, Finistere, France, reported a gust of 133 km/h (83 mph); the Netherlands gusts of 90 to 130 km/h (56 to 81 mph) along the Ijsselmeer coast; and southern Denmark the strongest wind recorded in the country’s history—a gust of 194.4 km/h (120.8 mph). By Tuesday morning, Windstorm Christian had dissipated considerably as it moved to Sweden’s east coast and out toward the Baltic Sea, although hurricane-force gusts of over 115 km/h were measured on the Baltic islands of Oland and Gotland.

Dr. Zuba noted: “October is usually a quiet month for windstorms in Europe. Nevertheless, the overall atmospheric conditions were favorable for storms to impact the UK and northern Europe. The damage from storms during this time of year can be more severe than storms that develop later because many trees still have leaves on their branches, making branches more likely to break off and become airborne missiles, and also making trees more likely to topple.

“Further, Christian, powered by the temperature gradient between cold polar air and warm subtropical air, strengthened as it traveled over the UK, France, Belgium, the Netherlands, and Germany.”

AIR also pointed out that Christian “had some similarities to a very powerful storm in October of 1987, which devastated the southeast coast of the UK. Although some of the recorded wind speeds of Christian were very high, the storm never reached the widespread strength of the 1987 storm.

“Christian’s track also resembles those of other significant historical storms, including 1990’s Daria, which was Europe’s most damaging storm in recent history; 1999’s Anatol, which was Denmark’s largest loss-causing event in recent history; and 2005’s Erwin. These storms also affected a large number of other European countries, including France, the Netherlands, Belgium, Germany, Sweden, and the Baltic countries.”

Dr. Zuba commented, “Christian produced record-setting wind speeds at several meteorological stations, but the total wind damage was less severe than that from the previously mentioned historical storms. This was a result of Christian’s smaller wind footprint and its passage over areas with fewer exposures.”

Residential and commercial structures across the affected area experienced relatively minor wind damage, and structural damage to well-constructed buildings was limited. AIR said this was consistent with the expectations of its engineers, as “nonstructural damage was observed to roofs, cladding, and other external building components, and wind-borne debris caused damage to windows. Heavier damage occurred from trees (many of which still had leaves on them) falling on buildings, cars, and power lines. In the UK, many claims resulted from power outages that destroyed food in freezers.”

AIR also said that its “damage survey team visited parts of northern Germany that were affected by the storm. Their preliminary findings indicate widespread tree damage, which caused severe damage to some homes and vehicles. The team observed generally minor wind damage to the roof tiles of residential and commercial buildings.”

However, the survey team did find that “significant damage occurred to agricultural buildings, which typically exhibit higher vulnerability than residential and commercial structures, and to light metal structures.

“While the size of individual claims is expected to be relatively low, the overall volume of claims is expected to be significant due to the size of the affected area. AIR expects that industry insured loss in Denmark will be highest, followed by Germany, the Netherlands, France, and the UK.”

AIR said its loss estimates reflect the following:
• Insured physical damage to property (residential, commercial, industrial, agricultural, auto), both structures and their contents.
• Losses to insured forestry in Norway, Sweden, and Finland

However, the loss estimates do not reflect:
• Business interruption and additional living expenses (ALE) for residential claims, for all modeled countries except the UK
• Losses to uninsured properties
• Losses to infrastructure
• Losses from non-modeled perils, including coastal surge and inland flooding
• Demand surge (AIR’s demand surge function is not triggered by this event)

Source: AIR Worldwide