Examining Extreme Weather Events: An Analysis of IMERG and Rain Gauges during Hurricane Florence

In 2018, severe storms and tropical cyclones cost the United States a total of 26.2 billion dollars in damage. Hurricane Florence, among one of the most costly tropical cyclones in 2018, arrived on the North Carolina coastline on September 14th. This hurricane slowly moved, almost stalling, dropping record rainfall in North and South Carolina. In recent years, the weather enterprise has encountered longstanding issues communicating to the public about slow-moving or stalled tropical cyclones associated with heavy rainfall in the United States. An example of a current communication issue related to slow-moving tropical cyclone is addressing a category 1 tropical cyclone may have the same flooding impacts as a category 5.

In anticipation of the large impacts of Hurricane Florence, USGS deployed numerous rapid-deploy rain gauges throughout the North Carolina area. CoCoRaHS rainfall gauge data was also collected during Hurricane Florence in North Carolina. In addition, the Integrated Multi-satellitE Retrievals for GPM (IMERG) from NASA’s Global Precipitation Measurement (GPM) satellite network system provided coverage over the same area using a 0.1 x 0.1 degree resolution grid of rainfall estimates in North Carolina during Hurricane Florence.

Improving our tools of prediction for these extreme weather events is essential for preparation and mitigation in the future. The primary goal of this research was to analyze and verify the accuracy of the Integrated Multi-satellitE Retrievals for GPM (IMERG) final run data product through NASA's Precipitation Processing System with real-time rainfall gauges during extreme events such as Hurricane Florence as well as daily rainfall during a 5-month period of July through November 2018. Additionally, this study will examine the economic impacts with a social science approach.