A polygon feature class of the county flood criteria boundaries within Miami-Dade County. The purpose of the Miami-Dade County Flood Criteria Map is to determine the minimum ground surface elevation of developed properties, crown/grade of roads, and secondary canal banks based on a 10-year, 24-hour storm event, 2060 scenario with SLR, and the minimum top elevation of seawalls, unless higher elevations are required by other regulatory applicable standards.Available for review and comment October 22, 2021 through December 22, 2021.Updated: Every 10 yrs The data was created using: Projected Coordinate System: WGS_1984_Web_Mercator_Auxiliary_SphereProjection: Mercator_Auxiliary_Sphere

A raster dataset of the county flood criteria boundaries within Miami-Dade County. The purpose of the Miami-Dade County Flood Criteria Map is to determine the minimum ground surface elevation of developed properties, crown/grade of roads, and secondary canal banks based on a 10-year, 24-hour storm event, 2060 scenario with SLR, and the minimum top elevation of seawalls, unless higher elevations are required by other regulatory applicable standards. Available for review and comment October 22, 2021 through December 22, 2021.Download County Flood Criteria Raster

This map represents Flood Insurance Rate Map (FIRM) data important for floodplain management, mitigation, and insurance activities for the National Flood Insurance Program (NFIP). The 100-year flood is referred to as the 1% annual exceedance probability flood, since it is a flood that has a 1% chance of being equaled or exceeded in any single year.

This nowCOAST™ map service provides maps depicting the latest official NWS Potential Storm Surge Flooding Map for any significant landfalling tropical cyclone expected to impact the Atlantic or Gulf of Mexico Coasts of the Contiguous United States. The map layers depict the risk associated with coastal flooding from storm surge associated with tropical cyclones.

The Potential Storm Surge Flooding Map depicts the geographical areas where inundation from storm surge could occur along with the heights, above ground, that water could reach in those areas. These potential heights are represented with different colors based on water level: 1) Greater than 1 foot above ground (blue), 2) Greater than 3 feet above ground (yellow), 3) Greater than 6 feet above ground (orange), and 4) Greater than 9 feet above ground (red). Two versions of this graphic are provided in this map--one with a mask (depicted in gray) identifying Intertidal Zone/Estuarine Wetland areas, and another version without the mask where Intertidal Zone/Estuarine Wetland areas are symbolized with the same colors as other areas.

Two additional layers are provided to depict 1) the full geographic extent for which the Potential Storm Surge Flooding Map is presently valid (the "map boundary"), and 2) Levee Areas, if any, within the affected area (symbolized with a black-and-white diagonal hatch pattern).

If the Potential Storm Surge Flooding Map is not presently active, all layers will be blank except for the Map Boundary layer, which will display a shaded region indicating the coverage area for any potential future graphics along with a text label indicating that the map is not presently active.

This map service is updated approximately every 10 minutes on nowCOAST™ to ensure the latest information is provided to the user as soon as it becomes available. Once issued, the Potential Storm Surge Flooding Map will be updated by NHC every six hours alongside each new Forecast Advisory for the associated tropical cyclone. However, due to processing requirements during the creation of this product, the flooding map becomes available approximately 60 to 90 minutes following the release of the associated NHC Forecast Advisory, at which point nowCOAST™ will acquire it and update this map service within the next 10 to 20 minutes (i.e., this product will be updated on nowCOAST™ within approximately 70 to 110 minutes after the associated Forecast Advisory is released). For more detailed information about layer update frequency and timing, please reference the
nowCOAST™ Dataset Update Schedule.

Background Information

Developed by National Hurricane Center (NHC) over the course of several years in consultation with social scientists, emergency managers, broadcast meteorologists, and others, the Potential Storm Surge Flooding Map is intended to depict the risk associated with coastal flooding from storm surge associated with tropical cyclones. On June 1, 2016 it became an operational product, issued on demand for certain tropical cyclones that are expected to affect the Atlantic and Gulf Coasts of the United States. The product is not available for tropical cyclones that may affect coastal areas in the Eastern or Central Pacific regions.

From the NHC Website:

"What the Map Takes into Account

The Potential Storm Surge Flooding Map is based on the NWS Sea, Lake, and Overland Surges from Hurricanes (SLOSH) model and takes into account forecast uncertainty in the tropical cyclone track, intensity, and wind field. The map is based on probabilistic storm surge guidance developed by the NWS Meteorological Development Laboratory (MDL), in cooperation with NHC, called Probabilistic Hurricane Storm Surge (P-Surge 2.5).

P-Surge 2.5 derives storm surge probabilities by statistically evaluating a large set of SLOSH model simulations based on the current NHC official forecast, and takes into account historical errors in the official NHC track and intensity forecasts. P-Surge 2.5 combines the results of hundreds of individual SLOSH simulations to calculate the statistical distribution, or probabilities of possible storm surge heights at locations along the coast. All major factors that influence the amount of storm surge generated by a storm at a given location are accounted for, including the hurricane's landfall location, forward speed, and angle of approach to the coast; the storm intensity and wind field; the shape of the coastline; the slope of the ocean bottom; and local features such as barrier islands, bays, and rivers. The Potential Storm Surge Flooding Map is created by processing the resulting 10 percent exceedance levels from P-Surge 2.5, or storm surge values that have a 1-in-10 chance of being exceeded at each location.

The Potential Storm Surge Flooding Map takes into account:

Flooding due to storm surge from the ocean, including adjoining tidal rivers, sounds, and bays Normal astronomical tides Land elevation Uncertainties in the landfall location, forward speed, angle of approach to the coast, intensity, and wind field of the cyclone

The Potential Storm Surge Flooding Map does not take into account:

Wave action Freshwater flooding from rainfall Flooding resulting from levee failures For mapped leveed areas - flooding inside levees, overtopping of levees

Potential storm surge flooding is not depicted within certain levee areas, such as the Hurricane & Storm Damage Risk Reduction System in Louisiana. These areas are highly complex and water levels resulting from overtopping are difficult to predict. Users are urged to consult local officials for flood risk inside these leveed areas. If applicable to the region displayed by the map, these leveed areas will be depicted with a black and white diagonal hatch pattern.

The intertidal zone, or generally speaking, the area that is above water at low tide and under water at high tide, will be displayed with a user selectable mask layer on the Potential Storm Surge Flooding Map. Locations of estuarine wetlands, or lands that are saturated with water, either permanently or seasonally, are also used to help define this mask layer. This mask layer will allow users to differentiate between areas that could experience consequential flooding of normally dry ground and areas that routinely flood during typical high tides. The intertidal mask will be depicted as gray on the Potential Storm Surge Flooding Map.

What the Map Represents

The Potential Storm Surge Flooding Map represents the storm surge heights that a person should prepare for before a storm, given the uncertainties in the meteorological forecast. The map shows a reasonable worst-case scenario (i.e., a reasonable upper bound) of the flooding of normally dry land at particular locations due to storm surge. There is approximately a 1-in-10 chance that storm surge flooding at any particular location could be higher than the values shown on the map. Roadways are included in the basemap layer for aiding in geographical referencing only. The map will not indicate which roadways may flood from fresh or salt water in a hurricane situation."

For more information about the NHC Potential Storm Surge Flooding Map, please consult the NHC Website or the associated NWS Product Description Document (PDD).

Time Information

This nowCOAST™ map service is not time-enabled.

References

NHC, 2016: Potential Storm Surge Flooding Map, NWS/NCEP National Hurricane Center, Miami, FL. (Available at https://www.nhc.noaa.gov/surge/inundation/).

NWS, 2016: Potential Storm Surge Flooding Map Product Description Document, NWS, Silver Spring, MD (Available at https://www.nhc.noaa.gov/pdf/PDD-PotentialStormSurgeFloodingMap.pdf).

A table of the Flood Zones.Updated: Every 10 yrs

A polygon feature class of the Coastal A Zone boundaries. Developed to aid the spatial location of the Coastal A Zones in Miami-Dade County for permitting purposes. Based on the Miami-Dade County Digital Flood Insurance Rate Map (DFIRM), effective September 11, 2009 published by FEMA and the ASCE 24 guidelines. 'Coastal A� Zone according to FEMA, is the area landward of a V Zone or landward of an open coast without mapped V Zones. In a coastal A Zone, the principal source of flooding will be astronomical tides, storm surges, seiches or tsunamis and not riverine flooding. During base flood conditions, the potential for breaking wave heights between 1.5 feet and 3.0 ft, will exist.Updated: Not Planned The data was created using: Projected Coordinate System: WGS_1984_Web_Mercator_Auxiliary_SphereProjection: Mercator_Auxiliary_Sphere

A polygon feature class of the Federal Emergency Management Agency (FEMA) Flood Insurance Rate Map (FIRM) map panels for Miami-Dade County.Updated: Every 10 yrs The data was created using: Projected Coordinate System: WGS_1984_Web_Mercator_Auxiliary_SphereProjection: Mercator_Auxiliary_Sphere

Last Revised: February 2018

Map Information

This nowCOAST™ map service provides maps depicting the latest official NWS Potential Storm Surge Flooding Map for any significant landfalling tropical cyclone expected to impact the Atlantic or Gulf of Mexico Coasts of the Contiguous United States. The map layers depict the risk associated with coastal flooding from storm surge associated with tropical cyclones.

The Potential Storm Surge Flooding Map depicts the geographical areas where inundation from storm surge could occur along with the heights, above ground, that water could reach in those areas. These potential heights are represented with different colors based on water level: 1) Greater than 1 foot above ground (blue), 2) Greater than 3 feet above ground (yellow), 3) Greater than 6 feet above ground (orange), and 4) Greater than 9 feet above ground (red). Two versions of this graphic are provided in this map--one with a mask (depicted in gray) identifying Intertidal Zone/Estuarine Wetland areas, and another version without the mask where Intertidal Zone/Estuarine Wetland areas are symbolized with the same colors as other areas.

Two additional layers are provided to depict 1) the full geographic extent for which the Potential Storm Surge Flooding Map is presently valid (the "map boundary"), and 2) Levee Areas, if any, within the affected area (symbolized with a black-and-white diagonal hatch pattern).

If the Potential Storm Surge Flooding Map is not presently active, all layers will be blank except for the Map Boundary layer, which will display a shaded region indicating the coverage area for any potential future graphics along with a text label indicating that the map is not presently active.

This map service is updated approximately every 10 minutes on nowCOAST™ to ensure the latest information is provided to the user as soon as it becomes available. Once issued, the Potential Storm Surge Flooding Map will be updated by NHC every six hours alongside each new Forecast Advisory for the associated tropical cyclone. However, due to processing requirements during the creation of this product, the flooding map becomes available approximately 60 to 90 minutes following the release of the associated NHC Forecast Advisory, at which point nowCOAST™ will acquire it and update this map service within the next 10 to 20 minutes (i.e., this product will be updated on nowCOAST™ within approximately 70 to 110 minutes after the associated Forecast Advisory is released). For more detailed information about layer update frequency and timing, please reference the
nowCOAST™ Dataset Update Schedule.

Background Information

Developed by National Hurricane Center (NHC) over the course of several years in consultation with social scientists, emergency managers, broadcast meteorologists, and others, the Potential Storm Surge Flooding Map is intended to depict the risk associated with coastal flooding from storm surge associated with tropical cyclones. On June 1, 2016 it became an operational product, issued on demand for certain tropical cyclones that are expected to affect the Atlantic and Gulf Coasts of the United States. The product is not available for tropical cyclones that may affect coastal areas in the Eastern or Central Pacific regions.

From the NHC Website:

"What the Map Takes into Account

The Potential Storm Surge Flooding Map is based on the NWS Sea, Lake, and Overland Surges from Hurricanes (SLOSH) model and takes into account forecast uncertainty in the tropical cyclone track, intensity, and wind field. The map is based on probabilistic storm surge guidance developed by the NWS Meteorological Development Laboratory (MDL), in cooperation with NHC, called Probabilistic Hurricane Storm Surge (P-Surge 2.5).

P-Surge 2.5 derives storm surge probabilities by statistically evaluating a large set of SLOSH model simulations based on the current NHC official forecast, and takes into account historical errors in the official NHC track and intensity forecasts. P-Surge 2.5 combines the results of hundreds of individual SLOSH simulations to calculate the statistical distribution, or probabilities of possible storm surge heights at locations along the coast. All major factors that influence the amount of storm surge generated by a storm at a given location are accounted for, including the hurricane's landfall location, forward speed, and angle of approach to the coast; the storm intensity and wind field; the shape of the coastline; the slope of the ocean bottom; and local features such as barrier islands, bays, and rivers. The Potential Storm Surge Flooding Map is created by processing the resulting 10 percent exceedance levels from P-Surge 2.5, or storm surge values that have a 1-in-10 chance of being exceeded at each location.

The Potential Storm Surge Flooding Map takes into account:

Flooding due to storm surge from the ocean, including adjoining tidal rivers, sounds, and bays Normal astronomical tides Land elevation Uncertainties in the landfall location, forward speed, angle of approach to the coast, intensity, and wind field of the cyclone

The Potential Storm Surge Flooding Map does not take into account:

Wave action Freshwater flooding from rainfall Flooding resulting from levee failures For mapped leveed areas - flooding inside levees, overtopping of levees

Potential storm surge flooding is not depicted within certain levee areas, such as the Hurricane & Storm Damage Risk Reduction System in Louisiana. These areas are highly complex and water levels resulting from overtopping are difficult to predict. Users are urged to consult local officials for flood risk inside these leveed areas. If applicable to the region displayed by the map, these leveed areas will be depicted with a black and white diagonal hatch pattern.

The intertidal zone, or generally speaking, the area that is above water at low tide and under water at high tide, will be displayed with a user selectable mask layer on the Potential Storm Surge Flooding Map. Locations of estuarine wetlands, or lands that are saturated with water, either permanently or seasonally, are also used to help define this mask layer. This mask layer will allow users to differentiate between areas that could experience consequential flooding of normally dry ground and areas that routinely flood during typical high tides. The intertidal mask will be depicted as gray on the Potential Storm Surge Flooding Map.

What the Map Represents

The Potential Storm Surge Flooding Map represents the storm surge heights that a person should prepare for before a storm, given the uncertainties in the meteorological forecast. The map shows a reasonable worst-case scenario (i.e., a reasonable upper bound) of the flooding of normally dry land at particular locations due to storm surge. There is approximately a 1-in-10 chance that storm surge flooding at any particular location could be higher than the values shown on the map. Roadways are included in the basemap layer for aiding in geographical referencing only. The map will not indicate which roadways may flood from fresh or salt water in a hurricane situation."

For more information about the NHC Potential Storm Surge Flooding Map, please consult the NHC Website or the associated NWS Product Description Document (PDD).

Time Information

This nowCOAST™ map service is not time-enabled.

References

NHC, 2016: Potential Storm Surge Flooding Map, NWS/NCEP National Hurricane Center, Miami, FL. (Available at http://www.nhc.noaa.gov/surge/inundation/).

NWS, 2016: Potential Storm Surge Flooding Map Product Description Document, NWS, Silver Spring, MD (Available at http://www.nhc.noaa.gov/pdf/PDD-PotentialStormSurgeFloodingMap.pdf).

This layer represents Flood Insurance Rate Map (FIRM) data important for
floodplain management, mitigation, and insurance activities for the
National Flood Insurance Program (NFIP). The 100-year flood is referred to as the 1% annual exceedence probability flood, since it is a flood that has a 1% chance of being equaled or
exceeded in any single year.

This layer was created as part of a Flood Inundation Map Library developed for display within the NOAA National Weather Service’s Advanced Hydrologic Prediction Services (AHPS). This data represents the potential flood extent for an elevation of 855.1 feet as recorded at the Great Miami River at Piqua, OH (Piqua, OH, OH; USGS ID 03262500) streamgage for the Great Miami River. This data is part of a series of inundation layers meant to correlate observations and forecasts from the river gages with a visual representation of areas impacted by high water. The dataset of flood depth grids was created from flood scenarios generated by HEC-RAS runs and LiDAR data obtained from the Ohio Statewide Imagery Program (OSIP). A raster of depth grids for each stage was created and subsequently merged to form continuous datasets for the main-stem Great Miami River. This data was developed to assist the public and emergency officials with planning and response to high water episodes at or near a defined National Weather Service river forecast point.

This layer was created as part of a Flood Inundation Map Library developed for display within the NOAA National Weather Service’s Advanced Hydrologic Prediction Services (AHPS). This data represents the potential flood extent for an elevation of 865.1 feet as recorded at the Great Miami River at Piqua, OH (Piqua, OH, OH; USGS ID 03262500) streamgage for the Great Miami River. This data is part of a series of inundation layers meant to correlate observations and forecasts from the river gages with a visual representation of areas impacted by high water. The dataset of flood depth grids was created from flood scenarios generated by HEC-RAS runs and LiDAR data obtained from the Ohio Statewide Imagery Program (OSIP). A raster of depth grids for each stage was created and subsequently merged to form continuous datasets for the main-stem Great Miami River. This data was developed to assist the public and emergency officials with planning and response to high water episodes at or near a defined National Weather Service river forecast point.

This two page document translated into Spanish serves as outreach material for the Little River Adaptation Action Area planning initiative led and created by Miami-Dade County's Office of Resilience (2021). The material summarizes what the project is doing, how residents can get involved, and provides a flood risk map illustrating potential flooding from stormwater rainfall and tidal flooding with two feet of sea level rise. The hand out also details various County assistance programs to enhance neighborhood and household preparedness and response to flooding events or emergency evacuation.

This 2-page handout translated into Haitian Creole introduces to residents and other stakeholders the Little River Adaptation Action Area planning initiative led by the Miami-Dade County Office of Resilience. The handout describes the purpose of the project, how to get involved and includes a map of stormwater and tidal flood risk with 2 feet of sea level rise as well as information about County resources and programs that can help hurricane preparedness and flood resilience home assistance.