What's an MCV (Mesoscale Convective Vortex)?

I've heard a few this evening comment on how the rain was supposed to hold off until later today, and what happened to our '80 degrees and sunny'?

Well, the rain and storm activity we had earlier this morning and afternoon was the result of an MCV, or Mesoscale Convective Vortex.  By definition, an MCV is a "low-pressure center within an MCS that pulls winds into a circling pattern, or vortex. With a core only 30 to 60 miles wide and 1 to 3 miles deep, an MCV is often overlooked in standard weather analyses. But an MCV can take on a life of its own, persisting for up to 12 hours after its parent MCS has dissipated. This orphaned MCV will sometimes then become the seed of the next thunderstorm outbreak. An MCV that moves into tropical waters, such as the Gulf of Mexico, can serve as the nucleus for a tropical storm or hurricane."

What?!? It basically means a smaller scale low pressure system that develops once a larger thunderstorm complex has dissipated.  Thunderstorms from Saturday night out west weakened, but formed an MCV which continued to feed off of the slight elevated instability found across Eastern Iowa and Illinois from the sunshine we had earlier.  If we were to animated the radar image above, you would have actually seen it spin in a counter-clockwise fashion - just how low pressure systems spin.  Often times, these small scale features are hard to predict/forecast, and can sometimes be the focus for additional convection downstream.  Sometimes, they can even aid in the development of severe weather.