Hydrology and Forecasting Using Experimental Satellite Flood Inundation Imagery at the North Central River Forecast Center

Flooding results in more fatalities and higher costs than any other type of natural disaster in the United States. In 2017, Hurricane Harvey alone caused widespread record flooding resulting in over 125 billion dollars of damages. The River Forecast Centers of the National Weather Service are charged with providing river forecast information to the nation, from flood to drought. Beginning in 2014, the North Central River Forecast Center began using satellite information from the experimental VIIRS Flood Inundation products as part of the JPSS Proving Ground and Risk Reduction program to monitor flooding over large areas. Results have proven this information to be reliable, providing a valuable new resource for flood detection and forecasting. Examples are provided to demonstrate the operational utility of the product not only for flooding from rainfall but also from ice jamming and cold region snowmelt scenarios. The primary limitation of this product is low temporal resolution at lower latitudes. This limitation is being overcome by obtaining information from more data sources such as the new launched NOAA-20 and GOES-16 satellites. The NOAA-20/VIIRS flood products provide flood inundation extent about 50 minutes later than Suomi-NPP/VIIRS. The availability of two polar-orbit satellites allows three 375m overpasses a day in the same region. The GOES-16/ABI flood products are available every 5 minutes in the CONUS at 1-km spatial resolution. Combining the information from these data sources provides more frequent imagery for flood mapping that compensates for cloud cover and presents an evolving picture of a flooding event over time. Examples of these flood products are shown and contrasted against single-source maps, demonstrating a significant improvement in the utility of satellite flood inundation products for practical hydrology and forecasting.