Between April 13th and 15th a major springtime storm system impacted central and eastern areas of the United States, bringing severe convective weather, thunderstorms, hail, tornadoes, flooding rains and heavy snow, resulting in damage across 20 states and economic and insured losses running into the hundreds of millions of dollars.
Impact Forecasting, the catastrophe risk analysis unit of reinsurance broker Aon Benfield, reports that while it remains too early to forecast the insurance and reinsurance industry losses from this outbreak of severe weather, with the impacts felt across such a wide swathe of the country the industry should expect minimally hundreds of millions of losses, perhaps more.
Convective storm damage was seen across 20 states, with 79 tornado reports, more than two dozen tornado touchdowns, 106 reports of large hail and 434 reports of strong winds, while at the same time torrential rains and heavy snowfall, blizzards and freezing rain also caused flooding damage and other impacts to property.
The most extensive tornado and thunderstorm damage was reported across Louisiana, Arkansas, Missouri, Mississippi, Florida, North Carolina, and Virginia, with Greensboro, North Carolina particularly badly hit by a tornado.
While tornadoes received the most media attention, Impact Forecasting said that it was straight line winds well in excess of 60mph that actually caused most of the damage, with communities from Texas to Wisconsin to Virginia and Florida all reporting severe damage to homes, businesses and vehicles.
Downed trees, powerline damage and large hail caused the majority of the impacts, the firm said, while at the same time torrential rainfall caused flash flooding across parts of the Deep South and the Mississippi River Valley.
In the same period, record levels of snowfall impacted the Rockies, Northern Plains and Upper Midwest along the northern stretch of the same primary low pressure system, with some reports of roof collapses due to the amounts of snow experienced, as well as freezing rain and other impacts.
Wildfires also sprang up in the southwest and southern Plains areas, with Oklahoma particularly badly hit and many structures destroyed in the hardest-hit counties of Dewey and Woodward.
Given the extent of the impacts from the weather systems that affected the United States during this period, Impact Forecasting said it will be some time before the economic and insurance or reinsurance industry losses are fully understood.
“Total economic and insured losses were expected to minimally reach the hundreds of millions (USD),” Impact Forecasting said, “Given the large footprint of impacts across most of the eastern two-thirds of the United States.”
Tornadoes in the United States are currently running well behind trend in 2018, but with much of the convective season to come there is plenty of time for the peril of severe thunderstorm or convective weather to create increasing losses for insurers, reinsurers and ILS specialists.