NASA Satellites Help Map Power Outages in the Carolinas from Hurricane Dorian

September 6, 2019

NASA Satellites Help Map Power Outages in the Carolinas from Hurricane Dorian

The Visible Infrared Imaging Radiometer Suite (VIIRS) on the Suomi NPP satellite captured this nighttime composite image as the storm approached the coast at 3:42 a.m. Eastern Time (07:42 UTC) on September 5, 2019.  Credit: NASA Earth Observatory

The Visible Infrared Imaging Radiometer Suite (VIIRS) on the Suomi NPP satellite captured this nighttime composite image as the storm approached the coast at 3:42 a.m. Eastern Time (07:42 UTC) on September 5, 2019.  Credit: NASA Earth Observatory

After devastating the Bahamas and grazing Florida and Georgia, Hurricane Dorian rebounded and raked the coast of South Carolina with strong winds, heavy rains, and a storm surge. Wind, falling trees, and flooding damaged power infrastructure in coastal areas of the southeast U.S.

The Visible Infrared Imaging Radiometer Suite (VIIRS) on the NASA/NOAA Suomi National Polar-orbiting Partnership (Suomi NPP) satellite captured this nighttime composite image as the storm approached the coast at 3:42 a.m. Eastern Time (07:42 UTC) on September 5, 2019. At the time, Dorian packed maximum sustained winds of 115 miles (185 kilometers) per hour and was moving north at 8 miles per hour.

The VIIRS sensor observed thick cloud bands circulating around Dorian’s large eye, the part of the storm with mostly calm weather and the lowest atmospheric pressure. Hurricane eyes average about 20 miles (32 kilometers); the National Hurricane Center reported Dorian’s eye had a diameter of 50 miles (80 kilometers) around the time this image was acquired. Thinner clouds—part of the storm’s higher-level outflow—extended well inland across Georgia, South Carolina, and North Carolina.

The VIIRS image was captured by the sensor’s day-night band, which detects light in a range of wavelengths from green to near-infrared and uses filtering techniques to observe signals such as gas flares, city lights, and reflected moonlight. Infrared observations from VIIRS were used to enhance the visibility of clouds. Optical MODIS satellite data was layered into the image to make it easier to distinguish between ocean and land surfaces.

Power outage map.

Credit: NASA Earth Observatory

It is not possible to identify the locations of power outages based on the VIIRS night light image alone. However, as of 2 p.m. on September 5, several utility companies and Poweroutages.us were reporting more than 240,000 outages in South Carolina. The hardest hit area was Charleston County, where companies were reporting more than 130,000 outages.

In the coming days, forecasters expect Dorian to move near or over the coast of North Carolina and then toward New England and Nova Scotia.

NASA Earth Observatory images by Joshua Stevens, using VIIRS data from the Suomi National Polar-orbiting Partnership, and power outage data courtesy of PowerOutage.us.