September is National Preparedness Month, a time for Americans to review their preparedness plans for disasters or emergencies in their homes, businesses and communities. It’s also historically the peak of hurricane season.
Early Thursday morning Hurricane Laura made landfall in Cameron, Louisiana as a Category 4 hurricane, with sustained winds of over 150 mph. Laura marks the 13th named storm of the 2020 Atlantic Hurricane Season, which has included four hurricanes and nine tropical storms. For a storm to be named it must have winds of 39 mph or greater.
And the season is likely to get even busier. The National Oceanic and Atmospheric Administration recently updated their forecast and now predicts the season will have 19-25 named storms, up from their previous forecast of 13 to 19. Seven to 11 of the predicted storms this season could become hurricanes with winds of 74 mph or higher. Three to six of the hurricanes could become major hurricanes with wind speeds of 111 mph or greater.
With half of the hurricane season still to go, it’s a good time to learn about hurricane preparedness by visiting Ready.gov or Listo.gov (en Español). In the meantime, the U.S. Geological Survey stands ready to provide the science to decision-makers that can help guide efforts to protect lives and property if another hurricane or tropical storm makes landfall this season.
Tropical storms, hurricanes and other large coastal storms can impact seaside and inland communities and ecosystems with high winds, storm surge, erosion and flooding. These forces can destroy buildings, roads and bridges and reshape the nation’s coastline.
When a major storm threatens to make landfall in the U.S. or its territories, the USGS provides comprehensive scientific capabilities and information that decision-makers, emergency responders and communities can use to help them prepare, cope with and recover from a storm. This includes the USGS’s ability to forecast coastal change; track storm surge, river and stream levels and flow; capture high-resolution ground elevation and topographic data; create detailed maps that can be used by disaster teams responding in the aftermath of storms; and measure coastal and inland flooding across entire regions.
Forecasting Coastal Change as a Hurricane Approaches
Before a storm’s expected landfall, USGS coastal change experts forecast how a storm may reshape the coastline using a sophisticated system they developed called the coastal change hazard forecast model.
The model provides detailed forecasts of a strong storm’s likely effects on sandy shorelines along the Atlantic and Gulf coasts. It predicts where protective sand dunes are likely to be eroded at their bases or overtopped by storm waves and where coastal areas behind the dunes could be inundated by seawater.
These forecasts can help emergency managers make critical decisions before a major storm strikes, including which areas to evacuate, which roads to use and where to position storm-cleanup equipment. The forecasts typically begin 72 hours before a storm is expected to make landfall, are updated based on the latest forecasts from the National Hurricane Center and are available at the USGS Coastal Change Hazards Portal. The site has recently been updated with new coastal elevation data that reflect sandy shoreline changes resulting from recent hurricanes and new scenarios of storm-induced erosion. This allows forecasts for the 2020 Atlantic Hurricane Season to be based on the latest information available.
Working with the National Weather Service, the coastal hazards storm team also updates forecasts for certain areas several times a day using real-time water levels from the weather service’s Nearshore Wave Prediction System. The team’s Total Water Level and Coastal Change Forecast Viewer displays results from a new model that currently covers about 1,865 miles of coastline in select areas from Florida to Maine. The model predicts the timing and height of water levels at the shoreline and potential impacts to coastal dunes. NOAA will use the predictions to help inform forecasters at the National Hurricane Center. As the program’s coverage area expands, the predictions will also be made available to National Weather Service forecasting offices and the public.
“We are working on expanding the Total Water Level Viewer to include the Gulf coasts of Texas, Alabama and the Florida panhandle, as well as additional areas along the Atlantic coast which will give us about 2,900 miles of total coastline coverage,” said oceanographer Kara Doran, USGS Coastal Change Hazards Storm Team leader. “We hope the new information will be publicly available sometime this season.”