downburst or tornado?

Friday night there were numerous warnings for severe thunderstorms, but the only major damage was from a storm that produced a powerful "downburst" that did some terrible damage in the Bladensburg area
Three weeks ago, on June 1, there was an equal number of warnings for tornadoes during a dangerous afternoon and evening, and there were a number of small, short lived tornadoes later confirmed by the National Weather Service. 
But here in the Washington area, severe thunderstorms, downbursts and straight line winds have done more damage over the years than any tornado.  Terrific advances in radar meteorology over the last 20 years (now with dual-pol)  have allowed us to see storm structure in small detail.  But while Doppler can "see" rotation in storms and even very small whirlwinds in the air above us, which technically might produce a small tornado and trigger a TORNADO WARNING and result in some minor damage, downbursts can produce winds of 100mph or higher and cause major damage.
http://www.wjla.com/blogs/weather/2012/06/downburst-or-tornado-what-happened-last-evening-around-bladensburg--15942.html