FEMA and Flood Factor are different risk assessments. Flood Factor may show a higher risk because it accounts for flooding from rain and the effects of climate change.

Overview

Your FEMA zone and Flood Factor® are independent risk assessments. While the findings of these models do not diverge starkly across the US, in some areas Flood Factor may show more or less flood risk than FEMA, simply because of differences in the methodologies employed. FEMA determines flood risk on the community level, their risk projections capture risk from a single 1-in-100 or 1-in-500 event from storm surges and overflowing rivers and streams. Flood Factor calculates flood risk on the property level, accounts for changing climate conditions, and considers the risk of flooding due to high-intensity rainfall.  

As a result, Flood Factor shows a more nuanced, property-specific flood risk, as opposed to a binary in-or-out of floodplain analysis from FEMA maps. Flood Factor uses publicly available flood risk information that shows how risk will accumulate and change over time. It is most powerful when used in conjunction with FEMA flood maps and other available state and local flood risk resources, and should be viewed as complementary to FEMA flood maps, which need to be used for building and permitting purposes. Individuals can search their address on First Street to find their property’s flood risk as well as their FEMA zone. 

Flood risk on Risk Factor

The methods used to create the First Street Foundation Flood Model bring together a number of resources and techniques already developed as inputs to understanding one’s flood risk. By combining these resources, the model represents flooding from multiple risks, such as rain, river, tidal, and storm surge flooding, while also integrating current and future environmental considerations all at a property level.  Adding to the full picture of flood risk, the model also recreated more than one hundred coastal and inland flood events over a 20-year period (2000-2019) to provide estimates of past flooding likelihoods.  This combination of precision and national scope allows for a more comprehensive flood risk tool than is currently available. 

FEMA flood risk

To date, the standard national comparison for flood risk is the Federal Emergency Management Agency’s (FEMA) Special Flood Hazard Areas (SFHA).  The FEMA SFHA models are currently the most popular flood-risk identification tool and are widely used by government, research, and private companies as a way to understand flood risk, price insurance premiums, and prepare for potential hazards. A property's FEMA zone designation is estimated on Flood Factor. 

The initial FEMA SFHA models are made for individual communities and are generally very high-quality, have been built to explicitly understand the risks to a standard 1-in-100 or 1-in-500 year flood event, and have been developed over many years to identify community flood risk based on local historical context. However, these models do not exist for the entire country, and their output also undergoes a series of adjustments and revisions based on local stakeholder feedback.  That means that the FEMA SFHA maps that get instituted are very rarely the same as the initial risk identified in the area. Couple that with the fact that the model is created to capture risk from a single 1-in-100 or 1-in-500 event, reliance on historical trends, and the lack of national scale, and you have opportunities for improvement in the communication of national flood risk.

Flood Factor vs FEMA

In comparison, the method used to create the flood risk visualized on Risk Factor expands flood risk mapping to the entire country by relying on an innovative Regionalized Flood Frequency Analysis (RFFA) approach. This approach makes use of traditional statistical matching techniques to model the characteristics of ungauged streams and river reaches across the country with known gauged characteristics to produce likely flow conditions with high confidence. Additionally, a core component of the model is the ability to also include pluvial (rainfall) events as probabilistic flood risks with depths and associated return periods in areas that are outside the modeled extents of FEMA studies.  Both the RFFA and pluvial flooding integrations have allowed for a model that captures risk that is generally not captured in FEMA SFHAs. 

To highlight the additional coverage of the risk identified by the First Street Foundation Flood Model, the 1-in-100 hazard layer, represents a 1% annual risk of occurrence, as compared to the same probability zones outlined by the FEMA SFHA zones. The results indicate that the Flood Model generally captures about 3 times the risk as the FEMA SFHA.  Interestingly, the two models align well along gauged river channels and FEMA SFHAs help provide a source of validation for the fluvial risk identified in the model.  However, the discrepancies indicate the practical need for a more comprehensive approach that was used to produce the statistics in this report.

The alignment of the Flood Model results with SFHAs in areas that are gauged and mapped by FEMA is important. This highlights the utility of the Flood Model as being in agreement with standard indicators of flood risk by building on trusted models, reports, and open data resources. To that point, this model relies heavily on data from the National Oceanic and Atmospheric Administration (NOAA), FEMA, the United States Geological Survey (USGS), the World Climate Research Programme (WCRP), and hundreds of local government resources.  As such, the Flood Factor risk results should be seen as an extension of existing resources developed with innovative and creative methods to comprehensively include geographic areas that may have been left out of alternative-risk models.  

Use First Street to understand your risk

FEMA flood maps identify over 1.1 million miles of flood hazard areas, and while the maps can provide detailed information for homeowners on their flood risks, they are not available everywhere. Risk Factor’s national flood model shows that flood risk is more widespread in the United States, with over 26 million properties at risk over the next 30 years. First Street also includes flood risk from extended periods of high-intensity rainfall, leading to urban stormwater flooding and storm surge. Additionally, future conditions are considered, such as sea level rise.

Without free access to accurate flood information, more Americans will unknowingly be at risk from the nation’s costliest natural disaster. First Street aims to quantify and communicate America’s flood risk. By making flood risk data freely available for all, individuals and communities can prepare for and mitigate risks before they become a reality. 

Press Coverage

CNN: Flood risk is growing for US homeowners due to climate change. Current insurance rates greatly underestimate the threat, a new report finds

The New York Times: Climate Threats Could Mean Big Jumps in Insurance Costs This Year

Bloomberg: Most Americans Don’t Have Enough Flood Insurance for Climate Change

Learn more

• Understand the differences between FEMA Flood Zones
• How is my Flood Factor calculated?
• How does Risk Factor determine flood risk if changing environmental factors are uncertain?
• Urban flooding
• Property value

Answers to frequently asked questions regarding Flood Factor scores, accuracy, probabilities, and understanding of our risk assessments.

FirstStreet.org is an online tool that makes it easy for Americans to find their property’s risk of flooding and understand how flood risks are changing because of a changing environment. Use First Street to learn the annual and cumulative likelihood of water reaching your home so you can prepare for and mitigate risks before they become a reality.

Are you seeking answers to property-specific flood questions?
Search your address to learn how flood risk may affect your home or business.

What is Flood Factor?

Flood Factor® is a free, easy-to-use online tool that makes it easy to learn about a property’s current and future risk of flooding, discover its flood history, and understand how its flood risk is changing over time because of a changing environment. A property's Flood Factor is not only a score ranging from 1-10, it is a comprehensive risk assessment including a property's thirty-year risk of flooding from high-intensity rainfall, overflowing rivers and streams, high tides, and storm surges. Properties with higher Flood Factors are either more likely to flood, more likely to experience high floods, or both. 

How accurate is Flood Factor?

Data on Flood Factor comes from the First Street Flood Model and was built upon decades of peer-reviewed research and developed in partnership with more than 80 world-renowned experts.  Like all flood models, it's intended to help identify potential flood risks, and Flood Factor users are encouraged to follow up with qualified professionals and supplement this information with additional research and documentation they might have.

The comprehensive model integrates all major flood types, from tides, coastal surges, rains, and rivers, and uses historical flooding events to validate risk. The model also considers future environmental changes, which FEMA itself has acknowledged the need to be integrated into its flood maps. 

How can I remove a property from Flood Factor?

Properties cannot be removed directly through FirstStreet; however, we encourage you to share information that could impact your property's Flood Factor. This includes community flood risk reduction projects such as levees, seawalls, and pump stations. If something looks like it is missing or incorrect, please let the Flood Factor know by using the Help Center contact forms.

How often is First Street Data updated?

The First Street team is continuously working to refine its flood methodology and incorporate new information into First Street. While the First Street experience is updated regularly, a full Flood Model refresh occurs annually. Please note, as First Street is updated, a property's Flood Factor, such as a score, may change. Learn more.

Why is my Flood Factor different from my neighbor’s?

Because Flood Factors are determined based on potential flood depths and 30-year flood likelihoods at the building level, they often vary across and within neighborhoods. Even next-door neighbors can have significant differences in flood risks, largely due to differences in elevation, proximity to water or wetlands, and proximity to flood risk reduction projects.

One way to understand differences in risks is to switch to the map view on the flood risk explorer. By zooming in close enough, users can see both buildings' outlines as well as different flood scenarios. Properties with minimal Flood Factors shouldn’t show any flood water reaching the building outline in any flood scenario. Buildings in contact with deeper floods, or those with higher probabilities of flooding, will have higher Flood Factors. Learn more.

Are personal flood risk reduction measures like raising my home considered?

At this time, a property’s Flood Factor is based on the likelihood of water reaching a building, and as such, personal adaptation features such as raised homes are not included in the calculation.

If a home already has flood reduction measures in place, it may reduce the risk to its structure. We encourage users to work with local floodplain managers or engineers to best understand what level of risk personal flood reduction measures are built to withstand. Learn more.

Why do FEMA and Flood Factor have different flood risk assessments for my property?

Your FEMA zone and Flood Factor are two independent risk assessments. FEMA flood maps are used to determine insurance and building code requirements, whereas the Flood Factor is used to determine flood risk to the specific home today and into the future. 

While the findings of these models do not diverge starkly across the US, in some areas Flood Factor may show more or less flood risk than FEMA, simply because of differences in the methodologies employed. Flood Factor calculates flood probabilities on the property level and accounts for changing climate conditions. A core component of the model is its ability to include rainfall events as probabilistic flood risks. 

As a result, Flood Factor shows a more nuanced, property-specific flood risk, as opposed to a binary in-or-out of floodplain analysis from FEMA maps. Flood Factor uses publicly available flood risk information that shows how risk will accumulate and change over time. It is most powerful when used in conjunction with FEMA flood maps and other available state and local flood risk resources, and should be viewed as complementary to FEMA flood maps, which need to be used for building and permitting purposes. Learn more.

How similar or dissimilar are FEMA and Flood Factor across the country?

FEMA flood maps identify over 1.1 million miles of flood hazard areas, and while the maps can provide detailed information for homeowners on their flood risks, they are not available everywhere. Flood Factor’s national flood model shows that flood risk is more widespread in the United States, with over 24 million properties at risk over the next 30 years. Flood Factor also includes flood risk from extended periods of high-intensity rainfall, leading to urban stormwater flooding and storm surge. Additionally, future conditions are considered, such as sea level rise. Learn more.

Why is flood insurance recommended for my property?

While only FEMA maps can be used to determine flood insurance and building code requirements, both FEMA and Flood Factor recommend insurance regardless of the severity of risk because flood insurance is one of the best ways to protect against financial losses caused by flood events. It is also important to note that flooding is not included in standard homeowners insurance. Learn more.

Flood insurance is available to homeowners, business owners, and renters throughout the nation. Although flood insurance is only required for properties in high-risk FEMA flood zones, about 20% of all flood insurance claims come from properties outside these zones.

Will Flood Factor impact my property value?

A home is often your largest financial asset. This is why Flood Factor is dedicated to defining and communicating the flood risk facing every home in America. Flood Factor can help you, other individuals, and communities prepare for and mitigate flood risks before they become a reality.

What if my home has never flooded?

While a history of flooding in the past can be a great indication that it is likely to flood again in the future, many homes with high flood risks have never flooded before. One reason for this is that changes in the environment are increasing flood risks across the country.

Sell a home with flood risk

Before selling your home, you may be required to disclose the known hazards associated with the property. Among other hazards, this may include current and historic flood risk, location within a designated FEMA flood zone, and current flood insurance coverage. The specific requirements for disclosures change state by state, so it is best to check with your local authorities for the specific regulation.  

An important factor in selling a home with flood risk is understanding the costs to potential buyers. If the property is in a high-risk flood zone as designated by FEMA and purchased with a federally-backed mortgage, the property owners would be required to purchase a flood insurance policy as well. Generally, these flood insurance policies are provided through the National Flood Insurance Program (NFIP). These premiums may be lowered through investments in the home, such as elevating utilities or the home structure itself. If the property has been affected by a federally-declared disaster, it may be eligible to be purchased by local government programs. 

The impact of flooding on renters

Major flood events can pose a serious safety threat to all members of a community, requiring evacuations and causing damage to its homes, businesses, schools, and infrastructure, like roads, electrical grids, and sewage systems. Although renters may not have to worry about damage to their buildings, major floods can still ruin their belongings and create mold and other health hazards. Renters may also be impacted by nuisance flooding that occurs frequently but isn’t associated with a major flood event like the king tides experienced in many coastal communities. Nuisance floods often disrupt day-to-day life by limiting sidewalk access or closing roads, parking lots, and parks.

Most renters' insurance policies do not cover flood damage, so renters may want to purchase flood insurance policies to help fiscally protect themselves in the event of a flood caused by storm surges, heavy rains, overflowing rivers, or broken levees or dams. Some fiscal risk may exist, however, as neither renters insurance nor flood insurance covers living expenses incurred if a flood necessitates vacating their home. It's important to understand available flood solutions before a flood ever occurs.

We are committed to accuracy and continue to grow, adapt, and update our risk models as new and better information becomes available.

Quarterly Data Updates

At First Street®, we aim to quantify and communicate America’s climate risk. By making flood, wildfire, wind, and heat risk data freely available for all, individuals and communities can prepare for and mitigate risks before they become a reality.

We are committed to the accuracy of our data and will continue to grow, adapt, and change our flood, wildfire, wind, and heat models as new and better information becomes available. As such, improvements to our models are included in quarterly data updates, while the flood model, wildfire model, wind model, and extreme heat model are updated annually. Sign up for our newsletter to learn about updates as they become available by clicking or tapping here.

Wind Model Updates

February 2023

• Launched wind risk from the First Street Wind Model on the First Street™ site. Properties can now look up risks from hurricanes, tropical storms, tornadoes, or severe wind storms. 

Extreme Heat Model Updates

August 15, 2022

• Released the First Street Extreme Heat Model, a first-of-its-kind, nationwide spatial temperature model that makes it easy for individuals to find a property’s heat risk and understand how heat effects will change over time due to environmental changes.

Wildfire Model Updates

May 16, 2022

• Launched wildfire risk from the First Street Wildfire Model on the newly created First Street site, which is a free online tool that makes it easy for anyone to find their property’s past, present, and future flood and wildfire risk.

Flood Model Updates

May 16, 2022

• Expanded the First Street Model to include Hawaii, Alaska, and Puerto Rico
• Improve address matching to allow for more flexibility in showing flood risk to properties other than single-family residential homes.
• Updated our scoring methodology. The specific depth and likelihood of flooding expected to reach a property are now used to determine the boundaries for each level of flood risk.

April 23, 2021

• Updated building characteristics (i.e. # of stories, units, basements, ground floor elevation) in some areas to more accurately reflect current findings which improved accuracy for default annual loss calculations for those properties.
• Updated property FEMA zones based on user-provided documentation
• Expanded historic flood methodologies to improve the accuracy of 3 historic hurricanes (Harvey, Florence, and Matthew). The updated models now include additional flooding caused by rainfall.
• Incorporated new high-resolution LiDAR elevation data provided by local officials in the Dallas-Fort Worth metro area
• Updated statistics for 1,600 previously unavailable properties in Georgia

February 22, 2021

• Added annual flood damage estimates for residential properties at risk 
• Added total annual flood damage estimates for neighborhoods, zip codes, cities, and counties

January 18, 2021

• Updated Flood Factors that better represent wetland conditions and incorporate the latest geographic data.
• Improved the accuracy and extent of flooding for several historic floods, including Hurricane Katrina.
• Analyzed and added millions of new properties to Flood Factor with improved statistical methods and issues identified by users.
• Updated FEMA designations to reflect LOMAs and LOMCs submitted by users in addition to more accurate FEMA zone data obtained from FEMA. 

Oct 30, 2020

• Improved our Flood Model by determining a property’s Flood Factor is most accurate when calculated based on the building’s footprint, or outline. As a result, the center of map pins has been moved from the center of a property to the building footprint.
• Added new property addresses via Mapbox in order to provide Flood Factors for as many properties as possible.
• Widened the boundary for coastal properties in order to fully capture all possible flood risk scenarios for these areas.
• Adjusted Flood Factor for properties in South East Florida to reflect all flood risk scenarios a property faces.
• Updated 2035 map flood layers for some areas.

September 16, 2020

• Added 2 million new properties on Flood Factor.
• Updated Flood Factor scores for some properties based on new and improved data on flood risk.
• Made additional coastal cities and counties with cleaner coastal flood layer visuals available.
• Removed areas that are currently under review based on new and improved flood risk data.

Site Improvements

Ongoing site enhancements aim to provide our users with the best experience possible on firststreet.org

February 27, 2023

• Launched Wind Factor™, and provided wind risk information that considers how a location’s likely exposure to high-speed winds is affected by climate change’s impacts. 

August 15, 2022

• Launched Heat Factor®, the first of its kind, spatial temperature model that determines a specific location’s exposure to extreme heat and considers how heat risks will change over the next 30 years due to the changing environment

May 16, 2022

• Created Risk Factor™ is a free, online tool that makes it easy for anyone to find their property’s past, present, and future flood and wildfire risk
• Launched Fire Factor®, the first public, peer-reviewed wildfire model to show how property-level flood risks change over time because of the environment

March 19, 2021

• Improved site and search speeds across Flood Factor. 
• Added new videos explaining Flood Factor fundamentals and the differences between Flood Factor and FEMA. 
• Modified the content on locality pages to highlight the percentage of properties at risk of flooding. 
• Modeled risk on the community level to show the severity of risk threatening access to utilities, emergency services, and transportation within a neighborhood, zip code, city, and county.

February 22, 2021

• Added the average annual cost of all potential flood damages this year and 30 years from now, based on a property's flood projections and the accumulation of those expected costs over time.
• Included the “adjust building details” tool in order for users to change the various inputs, such as the estimated value of a home, the presence of a basement, the number of stories, and ground floor elevation, to see how these factors affect the costs associated with flood damage
• Added the total annual flood damage estimates this year, and in 30 years to neighborhood, zip code, city, county, and state pages

January 18, 2021

• Enhanced maps on desktop to expand for a fully immersive experience.

December 3, 2020

• Included a zoom bar for the score map to allow users to view Flood Factors on a neighborhood and city level. 
• Improved the Flood Factor experience on mobile devices.

November 13, 2020

• Added a pin on score maps so users can easily identify their property at any zoom level.
• Optimized Flood Factor’s load time for an even faster experience.
• Updated some coastal areas to include a 50% probability. 

October 30, 2020

• Updated address information in order to improve the search experience.
• Updated map pins to be shown on top of building outlines (when possible).
• Added new and updated coastal cities and counties with cleaner coastal flood layer visuals on the Flood risk explorer in 2035 for properties in southeastern Florida.

Sep 16, 2020

• Added local Flood Factor score maps on property pages.
• Made copy updates in partnership with The Association of State Floodplain Management.

August 24, 2020

• Added the 5% likelihood of a property flooding to the flood risk explorer.
• Improved address search function on Flood Factor.

Want access to our data?

You can get access to the most comprehensive property-level flood, wildfire, and heat risk data set in existence.

For commercial use or non-profits, academics, or public sector professionals needing data at a property level, First Street Foundation provides access to property-specific flood, wildfire, and heat risk statistics for purchase. Learn more. 

For nonprofits, academics, and the public sector, aggregated flood, wildfire, and heat risk summary statistics are now available for public, noncommercial use through the AWS Registry of Open Data. Learn more.

Learn more

• First Street Foundation Flood Model Methodology
• First Street Foundation Wildfire Methodology 
• First Street Foundation Extreme Heat Model Methodology

If you believe your property’s FEMA zone is incorrect, a flood control feature is missing, or you have more information about a historic flood please reach out to us!

Flood Factor® is an online tool created by the First Street that makes it easy for Americans to find their property’s risk of flooding and understand how flood risks are changing because of a changing environment. First Street ’s flood model is, built upon the excellent work of FEMA, NOAA, NASA, USGS, and many others, as well as the established and peer-reviewed work of all of our flood model partners. Please let us know if FirstStreet.org is displaying an incorrect FEMA zone, if a flood control feature is missing, or if you have additional information regarding the impact of a historic flood. We are continuously working to refine our flood model methodology and incorporate new information into Flood Factor to ensure we are providing the best, most accurate picture of flood risk to our users.

Share information

The projections shown on Flood Factor come from the First Street Flood Model. We have made our flood model’s full technical methodology available to the public because we support scientific collaboration and data transparency. Like all flood models, its projections are intended to help provide a fuller understanding of flood risks, and we encourage you to supplement this information with additional data. We are committed to the accuracy of our data and will continue to grow, adapt, incorporate feedback, and expand our model over time, including an annual data update.

Data that will help improve the Flood Model

You know your property better than anyone! If you have information you think might be helpful to improve our Flood Model, please let us know by submitting a request through our contact forms. Please note that this information will not change your property's Flood Factor, but it can help improve the accuracy of the First Street Flood Model, and the information shown on Flood Factor. In order to improve our Flood Model, please reach out if you notice any of the following issues:

Incorrect FEMA Zone

If you believe Flood Factor has listed the incorrect FEMA flood zone for your property, please submit a Letter of Map Amendment (LOMA). The FEMA zone information listed on First street is currently an estimated zone. We recommend working directly with an outside company to acquire the Flood Determination Certificate for a property or to get the determinations reversed with a Letter of Map Amendment. Once submitted through our help center form, we can correct this information.

Missing flood control features

Our team is continuing to conduct research on flood control projects around the country and will be continually updating the model based on new information. While our database contains 23,000 features today, we acknowledge there are more to include and value your input!

If you have knowledge of specific completed projects, precise service area extents-of-flood adaptation infrastructure, or spatial data on flood adaptation infrastructure,  please help the team by providing any level of detail you can here. Certain information about flood control projects is particularly useful, such as: 

• Name of the flood control project
• The entity in charge of the project (local government, FEMA, USACE, etc.)
• Address or specific location  
• Images
• Links to local, state, or federal documents outlining project details, including the flood event it protects for
• A map showing the geographic area the project protects, including the physical location of the flood control project

New projects can be included in our next update to improve the model! If you would like to read about examples of flood control projects and how gray infrastructure works to alleviate flooding please review this article. 

Example of a levee; an embankment built to prevent the overflow of a river. Levees can also be built along low-lying coastal areas.

Missing historic flooding event

Flood Factor uses data from First Street, which has modeled 57 major river and storm surge floods in the U.S. from  2001 on and is continually adding more. Historic events in the First Street Foundation Flood Model are recreated using hydraulic models and public data sources. Historic river flooding events are recreated by analyzing historical USGS stream gauge readings during identified flood events and then compared to recorded high water marks and insurance claims of flooding made during that event. Coastal flooding events are recreated by analyzing storm surge, tides, coastal circulation, wind-generated waves, and geospatial analysis for specific storms, such as Hurricane Katrina. The recreation is then compared to recorded high water marks during the event. 

Aftermath of Hurricane Gustav - August 2008

If you have knowledge of specific historic flooding, we'd love to hear from you. We will investigate historic flooding in this area further and incorporate any new events determined into our future update. 

In order to include historic events in our Flood Model please reach out to us through our Help Center and provide:

• Dates the event took place
• Location of historic flooding
• Any pictures that may show the depth and damage of the flood
• News articles that describe the flooding your property experienced 

Naming Mismatch

We understand you may have questions regarding the names of locations related to your property. The First Street Foundation Flood Model matches parcel data from official government sources to address data collected from commercial sources. Naming conventions attached to specific parcels and addresses may not exactly match, resulting in naming discrepancies. Here is a link to the methodology behind our research.

If you have knowledge of specific location names, we'd love to hear from you. Please submit a ticket through the First Street Help Center that includes:

• A corrected address that includes the house number, street address, zip code, city, and state
• The incorrect address listed on FloodFactor.com 

We will review the issue further and be sure to update any issues found during a future update. Please take a look at how we update First Street data.

Learn more

• Flood Model Methodology - Calculating property-level risk

Frequently asked questions about wildfire risk assessments. 

What is Fire Factor?

Fire Factor® is the first-of-its-kind, comprehensive property-level wildfire risk assessment in the form of a risk score from 1 (minimal risk) to 10 (extreme risk), integrated into several real estate sites and developed by First Street. 

Fire Factor features comprehensive current and potential future wildfire risk data at the property level. The First Street Foundation’s Wildfire Model is based on the U.S. Forest Service’s (USFS) LANDFIRE fuels dataset, augmented with additional data sources and methodologies to facilitate a high-resolution and future-facing product. The model was developed in partnership with top climate scientists and modelers from leading organizations, including wildfire modeling and environmental think tank Spatial Informatics Group, fire modeling and investigations company Reax Engineering, environmental research and analytics firm Eagle Rock Analytics, and ecological modeling company Apex Resource Management Solutions. 

In addition to current risk, the model provides an analysis of how various climate factors will impact a property's wildfire risk over the next 30 years, so property owners have better insights into their home’s current and future risk for wildfire.

How accurate is Fire Factor?

First Street Foundation’s Wildfire Model helps make wildfire risk more accessible and transparent so homeowners, sellers, buyers, and real estate professionals can more easily understand and mitigate any potential wildfire risks. Similar to the ongoing enhancements to Fire Factor, First Street intends to work with the entire community to further refine, update, and adapt its wildfire model, to continue to make the data more accurate with new and better information.

If a wildfire risk score looks high or low to you, this is a great signal to reach out to a local expert to learn more, including strategies for how best to protect a home in any high-risk areas.  You can also find some wildfire solutions on Risk Factor™.

What is the difference between wildfirerisk.org and Fire Factor?

Government-driven national wildfire risk data is available at www.wildfirerisk.org from the U.S. Department of Agriculture’s Forest Service. However, the site was designed for community leaders, and not consumers, and is intended to compare risk nationally or between states/counties/communities rather than neighborhoods or specific addresses. USDA data also doesn’t adjust risk based on more recent fires or changing environmental conditions; their analysis considers only the current risk to homes, exposure type, wildfire likelihood, and vulnerable populations and is strictly based on observed wildfires prior to 2014. However, 45% of the wildfire damage that’s occurred since 1980 has happened in the last three years, so its risk data may be underestimated. 

First Street's Wildfire Model is based on the U.S. Forest Service’s (USFS) LANDFIRE fuels dataset and augmented with additional data sources and methodologies and developed in partnership with top climate scientists and modelers from leading organizations. It aims to fill USDA’s wildfire data gaps with risk breakdowns at the individual property and adjusted to account for recent fires. The First Street Wildfire Model also provides an analysis of how various climate factors may impact a property's wildfire potential future risk of fire over the next 30 years.

Are community fire-prevention measures included in risk assessments?

The First Street Wildfire Model captures thousands of up-to-date community fire-prevention measures that occurred in the last 10 years, such as prescribed burns, thinning, fire breaks, and other forest management practices, which helps reduce the fuel in these areas and is continually adding more as more preventative measures are taken.

How often are Fire Factor scores updated? 

We are committed to the accuracy of our data and will continue to grow, adapt, and change our Wildfire Model as we learn new and better information. As such, improvements to our Wildfire Model are included in quarterly data updates. Sign up for our newsletter to learn about updates as they become available by clicking or tapping here.

Where can I find the technical methodology for the Wildfire Model?

You can find the full detailed flood methodology on the First Street website. 

What is the difference between my property’s Fire Factor and its vulnerability?

A property’s vulnerability to wildfires is different from its Fire Factor. A property’s Fire Factor is based on the probability of burning or exposure to embers. While a property’s vulnerability refers to the amount of structural damage the home could sustain in the event of a wildfire. A property’s vulnerability is based on the home’s specific building characteristics. A home’s specific building characteristics reflect its ability to survive a wildfire, such as the size of the structure, slope of the property, materials, and building value. 

Building characteristics have different likelihoods of ignition at different flame heights. For example, a property whose roof is made of metal may be less likely to ignite if it is in a fire with shorter flame lengths. Metal roofing is non-combustible and offers Class A protection. 

While the parcel a home sits on may have a high likelihood of burning, the physical structure of the home may be less vulnerable and therefore more likely to survive a wildfire if it has a metal, non-combustible roof, which increases the structure’s ability to prevent ember or flame penetration to the home.  

Can I get access to the data used in the Wildfire Model?

Data is available at the property level and at aggregated geographies. Please visit our data page access page for more information on these options. Additionally, you can access additional “locked” risk information, claim your home, and purchase a property report by signing up for First Street

Where can I find information about fire insurance? 

One way to offset the cost of wildfire damage is to invest in fire insurance, which can help reduce your financial risk and allow you to recover more quickly after a fire. Most homeowners insurance typically includes fire coverage but in some areas, this will need to be purchased separately. Compare fire insurance quotes at Hippo.

Learn more

• Wildfire Solutions
• How is my Fire Factor calculated?
• Commonly used vocabulary on Fire Factor

Answers to frequently asked questions regarding a property’s Heat Factor, the cost of heat, and health risks associated with increasing temperatures. 

Heat Factor is a free online tool created by First Street that makes it easy for Americans to find their property’s exposure to extreme heat events and understand how heat effects will change over time due to changes in the environment. As global temperatures rise at the fastest rates ever recorded, it's important to understand what factors contribute to heat risk. Use Risk Factor to find property-specific heat risk assessments determined by our heat methodology for any U.S. address.

What is Heat Factor?

A property's Heat Factor is an indicator of its risk of extreme heat exposure over the next thirty years.  The model assigns each property a Heat Factor, ranging from 1 (minimal risk) to 10 (extreme risk). Heat Factors are based on the current average daily high temperature and humidity of a property’s specific location, and how much the average daily high temperature and humidity in that location is expected to grow over the next 30 years. The expected change in average high temperature is influenced by the changing environment. A changing environment means higher average temperatures and increased humidity, which has a compounding effect on heat indexes that make risky health impacts more likely. As the global temperature rises at a faster rate than at any point in the planet’s geological record, it is important to understand what factors contribute to heat risk. Learn more about the environmental factors increasing heat risk.

How accurate is Heat Factor?

The peer-reviewed First Street Heat Model is a first-of-its-kind, nationwide, spatial temperature model that shows the exposure of a specific location to extreme heat events based on the temperature, topography, land cover, and humidity in the surrounding area. The development of the model required an unprecedented partnership with top climate scientists and modelers from leading organizations along with top data scientists and technologists to ensure the data is accessible, accurate, and actionable. 

Where possible, data has been validated against historic temperature records and government records. All methods used by the First Street Extreme Heat Model have been submitted to scientific peer-review journals.

How can I remove a property from Heat Factor?

Heat Factor is a product of the First Street Foundation, a non-profit committed to making climate risk information free and accessible to all.  We are committed to the accuracy of our data and we’re continuously working to refine our Extreme Heat Model methodology and incorporate new information into Heat Factor. When additional information is submitted, it is reviewed, and if appropriate, incorporated into the model, and shown on Heat Factor during a scheduled update. 

However, Heat Factors are not assigned on a one-off basis, rather they’re derived from the inputs that go into our Extreme Heat Model. These inputs come from publicly available data, therefore, properties cannot be removed directly through Heat Factor. Therefore, the only way a property’s Heat Factor can change is if new information is submitted that changes the underlying inputs used in our Extreme Heat Model. We encourage you to share information that may impact the inputs used in our heat by submitting an email.

How often is Heat Factor updated?

The Risk Factor team is continuously working to refine the Extreme Heat Model methodology and incorporate new information into Heat Factor. While the Heat Factor experience is updated regularly, a full Extreme Heat Model refresh occurs annually. Sign up for our newsletter to learn about updates as they become available.

What are heat islands? 

Heat islands are urban or metropolitan areas that are much warmer than the surrounding area due to human activities. The temperature difference is usually larger at night than during the day, greatly increasing the cost of cooling for homes and businesses located in a heat island. Nevertheless, daytime temperatures within a heat island can vary by as much as 7 degrees from the surrounding neighborhood or area. Common causes of the heat island effect include; neighborhood construction materials, city planning, and layout, distance to water bodies and vegetation, and human activities. Learn more.

How can I reduce my risk? 

Heat-related illnesses are caused by water loss,  excess physical activity, and reduced nutrients which causes your core temperature to rise. Being prepared will allow you and your loved ones to remain safe during extreme heat events. Before an extreme heat event, learn how to recognize and prevent heat-related illness.

To mitigate the negative effects associated with exposure to extreme heat, explore heat solutions such as energy-efficient ways to prepare your home for the next heat wave. Making the right investments to protect your home can protect you from dangerous heat illness on extremely hot days.

How much can heat cost? 

The amount of energy required to cool a home depends on the number of cooling days estimated for a property and the degrees of cooling required to maintain a consistent indoor temperature. The number of cooling days refers to the number of days when the temperature is warmer than 70°F and therefore requires the use of air conditioning to maintain a comfortable indoor temperature. The warmer the temperature outside the greater degrees of cooling required. 

The cost to cool a home depends on the temperature outdoors and specific property characteristics such as the number of bedrooms, age of the home, and square footage. The price each household will pay for electricity varies depending on where the local grid is supplied, the companies that supply an area, and the number of homes. Using data on energy rates from Energy Information Administration (EIA), a property’s yearly energy consumption is translated into cost based on energy rates in that area. Learn more.

Please note, cooling days on Risk Factor only consider air conditioning, not other cooling devices such as fans. 

How can heat affect health?

Extreme heat can lead to dehydration, fatigue, heat stroke, heat exhaustion, and heat cramps, which occur as a result of the body’s inability to cool itself relative to the surrounding environment when heat indexes exceed certain physical thresholds. Heat Index Values are a measure of how hot it feels outside when incorporating relative humidity. 

Heat Index temperatures around 80 degrees are associated with relatively minor consequences, such as fatigue. Once the heat index exceeds 90 degrees, heat-related illnesses such as cramps, heat exhaustion, and heat stroke become possible. At a heat index of 100 degrees, early-stage heat-related illnesses such as cramps and heat exhaustion go from being possible to being likely for anyone who is exposed to heat for a prolonged period of time.  While heat-related illnesses can cause death at any heat index, a heat index above 125 degrees is particularly risky. At these temperatures, heat stroke is likely to occur for any individual exposed to these temperatures for a prolonged period of time. Learn more.

Learn more

• Heat Index

Understand the difference between Risk Factor, Risk Factor Residential Unlimited, Risk Factor Commercial and Residential Unlimited, and Risk Factor Portfolio and Data Unlimited.

Risk Factor reports include additional risk information beyond what is freely available via Risk Factor. Unlock access to a variety of interactive maps to help better understand a property’s risk, estimated damage costs based on a property’s unique risk, and the ability to customize your home’s characteristics to understand how adaptation and mitigation improvements would lower your risk.

Risk Factor, our original climate risk assessment tool, will remain free to use for residential properties, offering a basic climate risk assessment. Users can also “claim” one property for free to access an in-depth Risk Factor report.

Risk Factor Features

Building-specific risk information

Risk Factor provides more building-specific information. You have the ability to view the estimated damages a property may face from flooding or wildfire, the estimated days to repair or rebuild, estimated cooling costs associated with rising heat, carbon emissions, and more. You can also adjust your home’s characteristics to see how your home’s risk is affected by building material, number of stories, structure size, and more.

High-resolution interactive maps 

With Risk Factor, you unlock access to a variety of interactive maps to help better understand a property’s risk. These high-resolution maps allow you to visualize the extent and severity of flood, wildfire, and heat risk. You can use the interactive maps to understand the exact area that may flood and the depth of the water associated with a flood; visualize where flames from a wildfire may reach, how tall these flames may be, and the intensity of the forecasted wildfires; and identify urban heat islands and the impact they have on local temperatures.

Understand risk within your larger community

A home is only as valuable as the community it is a part of. Identify pockets of risk for residential or commercial buildings in your neighborhood. Know if your local utility or other critical infrastructure is at risk of being damaged or becoming inoperable. Feel confident that social infrastructure such as schools and places of worship aren't at risk.

Personal Use

Risk Factor Residential Unlimited

If you’re a homeowner or home buyer we suggest opting for Risk Factor to unlock single reports for specific properties you'd like to learn more about. Homeowners can benefit from Risk Factor by gaining a better understanding of their property’s risks and learning about impactful solutions to better protect their home and investment. Home buyers can leverage Risk Factor to make more informed buying decisions and understand where adaptation solutions may be necessary to protect their future homes.

Business Use

While commercial and public sector users can benefit from purchasing single Risk Factor property reports, they may find more use from the additional information and ability to purchase a large number of properties available with Risk Factor Unlimited or Portfolio plans. These plans can inform where to build and how to mitigate future risks, building design, purchasing decisions, and investment opportunities; ideal for commercial users who want a better understanding of the long-term climate risk of properties and investments. Risk Factor Unlimited and Portfolio can also be used by members of the public sector to target resilience policies, infrastructure planning, and managed retreat programs.

Risk Factor Commercial and Residential Unlimited

Commercial real estate professionals and those with multiple property holdings can upgrade to a Risk Factor Unlimited subscription, offering 12 months of unlimited nationwide search capability for residential and commercial properties. 

Risk Factor Portfolio and Data Unlimited

Risk Factor Portfolio and Data Unlimited provides unlimited search capability along with access to First Street Foundation’s underlying data and hazard layers through bulk delivery, enabling portfolio reviews or integration into personal data sets.  

Learn more

• Help with credits, payments, and billing
• What’s the difference between Risk Factor and Risk Factor?
• Risk Factor FAQ

Answers to frequently asked questions about First Street features and additional risk information.

The full First Street report provides building-specific, climate-adjusted estimates of damages and potential damages due to a building’s climate risk, and allows users to customize details about a building to get the most accurate estimate of risk. By providing comprehensive damage estimates, property and community levels of risk, access to risk data for commercial buildings, and the ability to personalize features, First Street provides risk information beyond what is freely available on FirstStreet.org.

First Street serves as a comprehensive climate risk assessment tool that can provide one-of-a-kind insights to homeowners, home buyers, commercial real estate owners, investors, designers, and developers. Click here to learn more about the different First Street plans to understand which is best for you.

Where can I see the properties I’ve unlocked?

Once you have created a First Street account, you can access any of your unlocked properties by clicking on Purchased Properties in the drop-down under your user icon on the upper right side of the screen. Be sure that you have signed into your Risk Factor account to view your purchased properties. 

How do I unlock a property?

First Street content and features are only viewable to First Street members who unlock properties either through a 7 day free trial or purchases. Reports are available for all properties and each property has a flood, wildfire, wind, and heat report. Once unlocked, members will be able to view all three reports for their property. 

You have the option to enter your credit card information or connect your Apple Pay or Google Pay account in order to start a 7 day free trial or purchase a subscription. To save your payment information for future purchases, check your Store credit card for future use.

How long do I have access to a property’s features?

You have access to a property’s First Street report for one year.

Publicly viewable residential properties vs non-publicly viewable commercial properties

Information for commercial or mixed-use properties is only available with First Street. First Street allows you to access additional risk information and features for residential properties. 

If you searched for a property that is classified as commercial or mixed-use or you want access to additional information and features for a residential property you must first create a First Street account. By creating a First Street account you can unlock access to a variety of interactive maps to help better understand a building’s risk, estimated damage costs based on a building’s unique risk, and the ability to customize property details to understand how adaptation and mitigation improvements would lower its risk.

How can I reset my password?

If you are unable to remember your password or would simply like to change it there are two options to reset your password:

1. Reset your password from the Account Settings page:

• • Click the Edit button under the Password field.
  • Fill in the Update your password pop-up form and click Save.
    
    

2. Reset your password from the Sign in page:

• • Click the Reset here link to reset your password.
  • Enter the email address associated with your account and click the Reset now link. A password reset email will be sent to your email address.
  • Open the email from Risk Factor and click the Reset password link.
  • You will be brought to a password reset page. Enter your new password into the required fields and click Reset password.
    
    

How do I cancel my subscription?

You can cancel an active subscription by going to the billing page. There you'll see a card with your current subscription, where you can click "Manage Plan".

Afterwards you'll be taken to a page where your current plan is highlighted, there can click "Cancel Plan" and a dialogue will appear asking for confirmation.

Where does the initial data on property details come from?

The initial property input data shown come from local assessor's offices and our 3rd party data provider Lightbox. However, you can customize this information to see how your home’s specific characteristics affect its risk by adjusting things like building material, number of stories, structure size, and more.

Can I share my unlocked property with someone else?

Although sharing is not included in the base subscription plan, it is available as a paid subscription add-on. This feature enables you to share an unlimited number of unlocked reports with others through personal links that can be viewed for free by those who do not have a subscription.

How can I adjust information on the public site?

You know your property better than anyone! If you have information you think might be helpful to improve our Risk Models, please let us know by submitting a request through our contact forms.

Please note that this information will not change your property's Flood, Fire, Wind, or Heat Factor, but it can help improve the accuracy of our models, and the information shown on Risk Factor.

In order to improve our Flood Model, please reach out if you notice any of the following issues:

• Naming Mismatch: Our models match parcel data from official government sources to address data collected from commercial sources. Naming conventions attached to specific parcels and addresses may not exactly match, resulting in naming discrepancies. 
• Missing Building Footprint: Risk is determined by a home’s building footprint. If the building footprint is missing, the risk is determined to the center of the property parcel. If the building footprint is not near the center of the property, the associated risk statistics may not capture all risks to the building structure. Click Flood Maps and view the Current & Future Risk layer. If the red pin isn’t over a dark grey shape outlining the physical structure of the building, the building footprint is missing. Note, it may be helpful to select the flood likelihood Very regular event - 50% likely to make sure the flood layer is not covering the footprint. 

• Incorrect FEMA Zone: If you believe Flood Factor has listed the incorrect FEMA flood zone for your property, please submit a Letter of Map Amendment (LOMA) to our help center. The FEMA zone information listed on First Street is currently an estimated zone. Once submitted through a help center form, we can correct this information.
• Missing flood control features: Our team is continuing to conduct research on flood control projects around the country and will be continually updating the model based on new information. If you have knowledge of specific completed projects, precise service area extents-of-flood adaptation infrastructure, or spatial data on flood adaptation infrastructure,  please help the team by providing any level of detail you can here.
• Missing historic flooding event: Flood Factor uses data from the First Street Foundation, which has modeled 57 major river and storm surge floods in the U.S. from  2001 on, and is continually adding more. If you have knowledge of specific historic flooding, we'd love to hear from you. We will investigate historic flooding in the area further and incorporate new information in future updates as appropriate. 

Learn more

• Help with credits, payments, and billing
• Which Risk Factor Plan is right for me?
• What’s the difference between Risk Factor and Risk Factor?