Lake Effect

On September 2, 2008, a narrow band of lake-effect rain showers set up and gave some precipitation to western portions of Winnipeg. The synoptic setup was just right, with 850 mb temperatures of about 3°C and lake temperatures around 18°C, exceeding the minimum threshold of a temperature difference of 13°C typically regarded as the minimum required to produce lake-effect precipitation.

Note how around 0000Z, the velocity animation shows lower speeds within the core of the heaviest rain--this is likely because of precipitation drag acting on the inner part of the precipitation band.
 
 
Base Reflectivity
 
 
Radial Velocity