With over 1.3 million residents, New Hampshire is no stranger to the impacts of natural disasters. The state is vulnerable to a wide range of natural hazards, from severe storms and flooding to winter weather events and dangerous wildfires.
Despite this reality, many residents of New Hampshire remain unaware of the full scope of the natural disasters that can occur in the state. This lack of awareness can be dangerous, leaving people ill-prepared to face the challenges that these events can bring.
That’s why this analysis is so important – providing information on the natural disasters that can occur in New Hampshire, including the worst events that have impacted the state since 2000.
Is New Hampshire At Risk of Natural Disasters?
Compared to the rest of the United States, New Hampshire has a shallow risk of natural disasters. Excluding COVID, New Hampshire has had 37 disaster declarations since 2000. Of these, 26 were declared major disasters.
New Hampshire is also sometimes hit by natural disasters, which cause more than $1 billion in damages. Since 2000, more than 7 separate $1-billion events have affected the state, including severe winter storms and tropical cyclones.
Worst Natural Disasters in New Hampshire By Cost (Since 2000)
- Hurricane Sandy 2012: $83.9 billion
- Hurricane Irene 2011: $17.7 billion
- 2016 Drought: $4.3 billion
- February 2015 Winter Storm and Cold Wave: $3.8 billion
- April 2007 Severe Weather and Flooding: $3.6 billion
Worst Natural Disasters in New Hampshire By Deaths (Since 2000)
- Hurricane Sandy 2012: 159 deaths
- Hurricane Irene 2011: 45 deaths
- February 2015 Winter Storm and Cold Wave: 30 deaths
- January 2018 Winter Storm: 22 deaths
- April 2007 Severe Weather and Flooding: 9 deaths
*Cost and death tolls are for the entire disaster, including in other states affected.
Most Common Natural Disasters in New Hampshire
New Hampshire has approximately 19,000 miles of rivers and streams. Snowmelt, heavy rains, and ice jams can cause these rivers to swell, resulting in widespread floods. Heavy rains can also cause deadly flash floods in the state. As a result, many areas of New Hampshire are at high risk when it comes to flooding. The state has had to declare a disaster twice because of flooding since 2000.
New Hampshire Flood Stats
- 64,900 properties at substantial risk in 2020
- 86,800 properties at risk by 2050
- 67,900 properties at substantial risk by 2050
- 28,400 properties at almost certain risk by 2050
- 13,800 FEMA flood damage claims since 2000
Which Areas of New Hampshire Are Most At-Risk of Flooding?
Floods can occur in all parts of New Hampshire, but some areas of the state are particularly at-risk. Below are New Hampshire areas with the greatest percentage of properties likely to experience flooding (based on 2020 calculations).
- Littleton: 27%
- Keene: 24%
- Laconia: 22%
- Hudson: 20%
- Lebanon: 19%
- Franklin: 15%
In addition to these areas, there are many cities and towns in New Hampshire where thousands of properties are at risk. This includes over 4,000 properties in Manchester and over 2,600 properties in Nashua.
Because of climate change, the risk of flooding is only increasing in many parts of New Hampshire.
2. Heavy Snowfall and Winter Storms
New Hampshire ranks #3 in the country for the most snowfall and #4 for the most snowfall days per year. Mount Washington in the White Mountains gets the most snowfall, with an average of 282 inches per year. Concord, NH, gets an average of almost 70 inches yearly, and Manchester, NH, averages over 67 inches yearly.
Snowfall in New Hampshire often comes down as snowstorms or blizzards. These winter storms can shut down businesses and travel, resulting in huge economic losses. Since 2000, the state has been affected by three billion-dollar winter storms.
New Hampshire Winter Weather Stats
- Average snowfall per year: 71″
- Snowfall days per year: 95 days
- Coldest recorded temperature: -47°F on Mount Washington in 1934
- Record snowfall: 49″ on Mount Washington on February 25th, 1969
3. Freezing Rain
The climate of the Northeast makes it ideal for freezing rain. In New Hampshire, some areas have up to 18 hours of freezing rain annually. This makes New Hampshire one of the highest-risk states in the USA for freezing rain.
Freezing rain most frequently occurs during December and January, but fall and spring freeze events also happen. Icy road conditions from the rain make vehicle accidents and slip and fall injuries common. It’s also common for people to lose power during freezing rain events, meaning that thousands can be left without a way to heat their homes during the coldest months.
4. Heat Waves
As with the rest of the country, the risk of heat days is increasing in New Hampshire. New Hampshire has almost no “dangerous” heat days per year. The National Weather Service defines these as days where the heat index is 103F or above. By 2050, the number of dangerous heat days in New Hampshire is expected to increase to 5 days per year.
In addition to more dangerous heat days, New Hampshire will also see more “Local Hot Days.” Local Hot Days are defined as “Days at or above the 98th percentile temperature, or the temperature than an area could expect to see on the hottest 7 days of the year.” Essentially, Local Hot Days factor in what temperatures a local population is used to experiencing.
An increase in Local Hot Days is associated with health problems like strokes, and heat-related deaths are more likely to occur. Energy demands also increase from air conditioning use.
All parts of New Hampshire are expected to have an increase in Local Hot Days, but Sullivan County is particularly at-risk. By 2053, Sullivan is expected to have 17 consecutive days with temperatures at or above 91.5℉.
A large portion of New Hampshire is covered in forests. However, it is a wet state with lots of rainfall, so wildfires are uncommon. When wildfires do occur, they are usually small and quickly contained.
Because of climate change, the risk of wildfires in New Hampshire is growing. By 2050, an estimated 12% of all properties in the state will be at risk of wildfire.
New Hampshire Wildfires Stats
- Acres burned in 2021: 96
- Number of fires in 2021: 280
- Percentage of state covered by forests: 84%
- Number of properties currently at risk of wildfire: 26,238