NWS Louisville Doppler Radar Cell Trends

Tracking Two Storms Impacting the Northern U.S. Through Thanksgiving and into This Weekend

Heavy lake effect snow, gusty winds, and localized blizzard conditions will persist through Thanksgiving near and downwind of the Great Lakes. Rain and mountain snow are forecast for the Pacific Northwest. Confidence is increasing for another winter storm to develop over the northern and central Rockies Friday and track across the central Plains through the Midwest and Great Lakes this weekend. Read More >

NWS Doppler Radar (WSR-88D) Example Products

NWS Doppler radar has various software algorithms which derive temporal and spatial trends in thunderstorms and other precipitating entities. Such algorithms help identify trends that may support and provide guidance into severe weather warning decision process.

In the image, supercells on March 2, 2012 are shown over Clark County, IN and northern Trimble County, KY. At the bottom is a cell trend table with statistics on a number of storms across central Kentucky and southern Indiana. Statistics are color coded depending on values and thresholds. Clicking on any statistic pops up a trend graph for a selected storm. Shown are graphs for 1) reflectivity values (upper left) where values increase to 70 dBZ (very high), 2) digital VIL (middle left) where values are high around 70, 3) probability of severe hail (POSH; lower left) where values increase to 100 pct, and 4) maximum estimated hail size (middle top) where values are around 2.5 inches (which can be a slight overestimate). Similar graphs are available for other storm elements.