Using Webcam Imagery in Operations for the Surprise Snowstorm of 3 March 2016

Personal and publicly owned webcams are becoming more commonplace and affordable. At National Weather Service (NWS) Louisville, 150 cameras are monitored consistently for situational awareness across central Kentucky and south-central Indiana. These observations are a great asset to operations, especially in areas where radar and other observational coverage is not ideal.

In a case this past winter, computer models initially forecast a rain system to move through the region with surface temperatures in the 40s. However, as the system became imminent, the High-Resolution Rapid Refresh model began to show a better chance that dynamic cooling aloft would lead to snow, including warning-criteria amounts. As the event unfolded, bands of heavier precipitation developed. Area webcams displayed narrow swaths of heavy snow within these bands. It soon became apparent that a rapid forecast update needed to be collaborated with neighboring NWS offices. This change resulted in an upgrade to a Winter Weather Advisory for the Louisville forecast area, with a Winter Storm Warning for Eastern Kentucky counties. The webcams were crucial in identifying when snow began to fall and accumulate owing to the high snowfall intensity, despite initially warmer ground temperatures.