Storm Henri weakened prior to landfall, heavy rainfall & flooding widespread

Hurricane Henri weakened back into a tropical storm before making landfall yesterday in Rhode Island, but 140,000 homes are reported without power across the northeast and flash flooding affected parts of New York, New Jersey and the Tri States, with more heavy rainfall from Henri forecast for today.

Henri’s weakening prior to landfall could be a significant factor in the eventual insurance and reinsurance market loss, as it becomes more of a water than wind event.

However, the rainfall related flooding has been particularly bad in some areas of New York and New Jersey, as even prior to Henri coming ashore the feeder bands from the hurricane brought tropical moisture and drove record rainfall levels even in central Manhattan.

Flooded properties have been seen across a wide swathe of the region, including city areas from Brooklyn to Hoboken.

The result will be a significant insurance loss event from water related impacts, it seems, although how much would flow to reinsurance capital remains to be seen and the National Flood Insurance Program (NFIP) will be responsible for a reasonable share, it’s assumed.

Henri came ashore as a tropical storm with 60 mph sustained winds and 70 mph gusts near Westerly, Rhode Island yesterday.

The storm surge has not been reported to have caused significant inundation or damage, although some coastal flooding was seen and some properties affected, according to media reports.

While Henri brought back memories of superstorm Sandy for some, the eventual wind-field that came ashore was both weaker and far smaller, at around a quarter of the size of Sandy’s.

However, strong wind gusts and torrential rainfall in an area already saturated by recent storms and rain has exacerbated the flood and water driven damage potential with Henri.

The rainfall threat persists as a weakened tropical depression Henri now moves through the northeastern states, with further flooding warned for today, Monday.

As Henri stalled and turned, before heading back east, rainfall has been prolonged in some areas and this is expected to be a factor through today as well.

The NHC continues to warn of isolated maximum storm rainfall totals of 10 to 12 inches across parts of northern New Jersey into southern New York, while more widely 4 to 6 inches of rainfall are anticipated.

Brooklyn has seen 8 inches of rainfall already, while Midtown Manhattan has seen over 6 inches. Parts of New Jersey have also already seen over 8 inches of rainfall.

In terms of wind speeds, the peak recorded were around 70 mph in Rhode Island, but parts of New York state saw over 65 mph gusts as well.

Right now it does appear that even a weakened storm Henri is still capable of producing an insurance industry loss into the very low billions of dollars, once all the damages are counted, given the high-value and populated regions affected.

But with flood a significant factor it becomes more difficult to establish where losses may fall, in terms of the share taken by the NFIP, as well as how much could fall to reinsurance capital.

Henri’s weakening before landfall and then rapid weakening after, with rain as a significant driver of loss, may reduce the chances of any major impact to ILS funds and their positions.

As we explained on Saturday, ILS fund manager Twelve Capital warned that the loss from Henri could be in the billions, but that impacts to its ILS funds would likely be restricted to aggregate deductible erosion.

It does seem possible that the industry loss comes out beneath the billion dollar mark, as losses increasingly look set to come from the flooding, rather than wind side of storm Henri.