Hurricane Sandy

The aftermath: 2019 anniversary update

In the seven years since Hurricane Sandy made landfall, the US has experienced multiple costly hurricanes, including Hurricanes Harvey and Maria in 2017 which have since surpassed Sandy in economic costs. However, despite this, Sandy still holds a significant place in US hurricane history.

At the time, the National Geographic described Sandy as a "raging freak of nature", causing 147 fatalities and widespread property damage across the US, Canada and the Caribbean (National Geographic, 2019; Britannica, 2019).

Sandy brought widespread flooding, landslides and strong winds to locations along the US eastern seaboard, with loss estimates revised over the years to USD $73.5 billion (NOAA, 2019). This makes Sandy the third costliest hurricane to make landfall on the US mainland and the fourth costliest hurricane to make landfall in the US since records began (NOAA, 2019).

However, despite Hurricane Sandy’s widespread financial impacts, some of which are still being felt today, the US continues to be dangerously susceptible to the consequences of hurricanes and coastal flood risk.

According to a recent NOAA report, the biggest increases in coastal flood in the US are concentrated on the east coast - the same area affected by Hurricane Sandy in 2012 (NPR, 2019). Several major urban areas are now projected to lie below sea-level in the future, making them particularly susceptible to the type of extreme storm surges caused by Sandy. According to one study that investigated rising sea levels in 414 US cities, Florida contains at least 40 per cent of the people who live on land potentially threatened by coastal flood (Huffington Post, 2015).

In fact, urbanisation is increasing in these flood-prone areas. Climate Central found that one-third of coastline states that may experience a 10% risk of ocean inundation each year by 2050 saw more new housing developed in coastal areas than on higher ground (VOA, 2019).

This increase in urbanisation in flood-prone and hurricane-prone areas is particularly concerning given the low rates of insurance penetration in the US: approximately 85% of US homeowners lack flood insurance (Insurance Business America, 2018). In Florida, an estimated 2.8 million family homes are at risk to storm surges, similar to the ones caused by hurricanes, but flood insurance premiums actually decreased from 2017 to 2018 (Carrier Management, 2019).

It’s clear that although seven years may have passed since Hurricane Sandy, lessons can still be learned. The US remains at risk from the effects of hurricanes and flooding, and strides must be made in land use planning, insurance take-up and flood management to ensure we don’t experience the same devastating impacts of Sandy (or Harvey) in the future.

Get in touch for more information about our event response work and flood data for the US. You can read the original event report below.

1 November 2012

Millions of homes and businesses were destroyed or damaged by post-tropical storm Sandy as it made landfall on the US east coast on 29 October, 2012, after sweeping up through the Caribbean. With a full moon on Monday 29 October causing a spring tide, Sandy brought a surge to the Eastern Seaboard that was over 13ft (3.9m) high in some places.

Insurance impacts

Following an otherwise relatively quiet hurricane season in the US, the financial impact of Sandy is still being assessed, but considerable damage has been caused over a wide area due to the exceptionally large wind field and wide range of factors involved.

Damage has been caused by wind, sea surge flooding, flooding from intense rainfall and electrical fires. Claims from winter storm damage from snowfall and cold weather as far north as Canada are expected from where Sandy moved northwards. Snow up to 5ft (1.5m) deep has already been reported in West Virginia.

Insured loss estimates currently range up to $20 billion, which would place Sandy among the most expensive hurricanes to have affected the USA. However, these figures remain highly uncertain and estimates will doubtless change as both the damage caused by the storm and the associated policy wordings in insurance contracts are clarified in the coming days. Complexity is expected in relation to policy terms applied to claims, not only because of the complex mix of possible loss causes but also because Sandy was downgraded from a hurricane to a post-tropical storm before it made landfall in New Jersey.

"Frankenstorm": A Meteorological Monster

Meteorologically, Hurricane Sandy was one of the most extraordinary storms in history. As the eighteenth tropical storm and the tenth hurricane of the 2012 season, it is likely to be one of the largest storms on record at time of writing, at over 1,000 miles across. It was the deepest hurricane to hit the northeast coast of the USA since the Long Island Express Hurricane (also called the New England Hurricane) of 1938.

Tropical storm Sandy developed from an area of low pressure in the Caribbean Sea on Monday 22 October 2012 and was thereafter upgraded to a hurricane on Wednesday 24 October. On the same day, Hurricane Sandy made a first landfall near Kingston, Jamaica, with winds of 80mph. After crossing Jamaica, Sandy strengthened and on Thursday 25 October made a second landfall in Santiago de Cuba, eastern Cuba, as a category 2 hurricane with winds of 110mph. While heading through the Bahamas, Sandy briefly weakened to a tropical storm on Saturday 27 October before re-intensifying back up to hurricane strength. Sandy was declared a post-tropical storm shortly before landfall near Atlantic City, New Jersey, at 8pm EDT on Monday 29 October.

As Sandy approached the north-eastern coast of the USA, the warm moist air circulating in the hurricane met cold air spreading south into northeastern USA from Canada (a nor’easter storm). This gave the storm additional energy, allowing it to strengthen and produce severe winds, heavy rain and blizzard conditions as it made landfall. The combination of a tropical storm with a passing frontal system is not unusual and is known to potentially increase the intensity of a storm, which is what happened as Sandy approached the US coastline.

Sandy rapidly weakened as it headed west across Pennsylvania and was classified as a remnant low on 31 October.

Western Atlantic Journey

As Sandy swept out of the Caribbean, by then Category 1, a state of emergency was declared first in New York, then in New Jersey, with NYC public transport shutting down from Sunday evening ahead of the hurricane’s predicted landfall on Monday. By that time, Sandy was 940 miles across, by far the largest windstorm on record to have hit the region.

After Sandy made second landfall on Cuba as a Category 2 hurricane, the mayor of New York City announced “Zone A” evacuation zones for low-lying areas of NYC that afternoon, as it became clear that Sandy was headed for the north-eastern coast of the USA.

As Sandy started to turn north-west and head for the US coast, the storm surge in Manhattan rose to 13.9ft (4.2m), more than 3ft (0.9m) higher than the previous record set in 1821. Maximum sustained wind speeds were 90mph by late Monday morning and the NY borough of Queens was underwater. New Jersey, already heavily flooded, was set to bear the brunt of Sandy’s arrival, but the effects of the storm were already evident in Maryland, Delaware, and other nearby states. In Rhode Island, the storm surge reached 6ft (1.8m) while still two hours before high tide.

US Landfall and Journey Overland

By 7pm October 29, Sandy was reclassified to a Category 1 post-tropical cyclone. It made landfall minutes later near Atlantic City, NJ. Many parts of New Jersey were by that time underwater and damaged or destroyed, including the Atlantic City casinos and famous boardwalk. The last tunnel out of Manhattan was closed just over an hour later, as tunnels and subways began to be infiltrated with floodwaters. 

Flooding went on spreading through the night as Sandy continued north-west. Breezy Point, in the NY borough of Queens, caught ablaze with an electrical fire that eventually destroyed around 100 homes. 7.4 million homes awoke on Tuesday without power and NJ governor Chris Christie described the Jersey Shore damage as “unthinkable”. Hundreds of miles from Sandy’s devastating centre, Chicago surfers were reported to be riding the 20ft (6m) high waves generated on Lake Michigan by the storm.


Carrier Management. 2019. 2019 Private Flood Insurance Report. [online] Available at: [Accessed 28 October 2019.]

Encyclopaedia Britannica. 2019. Superstorm Sandy. [online] Available at: [Accessed 28 October 2019.]

Huffington Post. 2015. More Than 400 U.S. Cities May Be ‘Past The Point Of No Return’ With Sea Level Threats. [online] Available at: [Accessed 28 October 2019.]

Insurance Business America. 2018. Private insurers and NFIP must work together to close gap. [online] Available at: [Accessed 28 October 2019.]

National Geographic. 2019. Hurricane Sandy, Explained. [online] Available at: [Accessed 28 October 2019.]

NOAA National Centers for Environmental Information (NCEI). 2019. U.S Billion-Dollar Weather and Climate Disasters. [online] Available at: [Accessed 28 October 2019.]

NPR. 2019. High-Tide Flooding On The Rise, Especially Along The East Coast, Forecasters Warn. [online] Available at: [Accessed 28 October 2019.]

VOA News. 2019. As Sea Levels Rise, Homes Sprout in US Flood Zones. [online] Available at: [Accessed 28 October 2019.]