Here's why D.C. is facing a severe-weather threat today: A low pressure system that's been dominating the country for the past four days.
Want to know why D.C. had thunderstorms for breakfast (and could have more for dinner)? Here's a big reason: This Jurassic-sized vortex that's totally dominating the central part of the country.
The cyclone is known as a cutoff low because it is spinning independently of the main circulation of the jet stream. Cutoff lows can really bring down the weather mood of a nation; you can read more about their dampening effects in last week's video discussion by ABC7 meteorologist Devon Lucie. This cutoff low, which was accurately predicted by the National Weather Service more than a week ago, has been sitting in place and twiddling its thumbs, so to speak, for the last 96 hours. The result has been rain, rain, and BOOM! Thunder, as you might've heard this morning.
Thanks to the satellite tech of NOAA and NASA, the entirety of this dismal system's being can be visualized in the form of water-vapor imagery. Seen below is an animation of the low's movements from Sept. 23 to Sept. 27, a ceaseless churning as if nature is trying to make an whopping bowl of mayonnaise.
Want to know when it's going away? Some United States residents can expect the clouds to vanish as early as tomorrow, when the system should begin to decay. But the sun doesn't come out in the D.C. forecast until Friday.