tornadic thunderstorm schematic.jpg

Idealized schematic plan view of a tornadic thunderstorm at low levels. Dark red shaded area shows the position of the main thunderstorm updraft (UD) Light blue shaded areas show the Rear Flank Downdraft (RFD) and Forward Flank Downdraft (FFD). Light-green line shows the probable extent of a radar echo. Black arrows shows the storm-relative flow (i.e. wind vectors with the mean northwesterly storm-motion subtracted). Frontal symbols mark the boundary between the warm inflow and cold outflow - areas of rising motion along the frontal boundary are shaded light-red. The likely location of tornadoes is indicated by the circled Ts.