Using cell-based vertically integrated liquid density to identify severe-hail thunderstorms in the central Appalachians and middle Ohio Valley

United States, National Weather Service,

"Vertically integrated liquid (VIL) as an indicator of thunderstorm severity has been studied by researchers since the early 1970s (Greene and Clark 1972). With the arrival of the WSR-88D radar, VIL became operationally available at offices with warning responsibility as a tool for gauging the potential severity of thunderstorms. VIL density has also been shown to be useful in efforts to identify thunderstorms that have a high potential for producing severe hail (Troutman and Rose 1997, Amburn and Wolf 1997). However, for severe hail producing thunderstorms, a threshold VIL density was shown to be more consistent from season to season, and day to day than a threshold VIL (Amburn and Wolf 1997). A threshold VIL density that could be used operationally at NWSFO Charleston WV was desired. However, previous studies done in different geographical areas have shown some variation in specific threshold grid-based VIL density values, with positive but differing amounts of success. With this in mind, a local study of VIL density was undertaken at the National Weather Service Forecast Office (NWSFO) Charleston WV, using data from the KRLX WSR-88D located in Ruthdale, 6 miles south of Charleston"--Introduction.

Technical Attachment

National Weather Service (NWS)