sentences:  The preceding atmospheric state was one of La Niña conditions, the cold phase of ENSO, which favors a storm track from the Ohio and Tennessee Valleys into the Appalachians.The cyclone initially formed in southeast North Carolina near a cold front on the morning of November 24 as the main cyclone over the Great Lakes weakened.Rapid development ensued as the surface center began to migrate back into a closed 500 hPa-level (14.75 inHg) (around 6,000 m/20,000 ft above sea level) cyclone, and the cyclone bombed while moving north through Washington D.C. the next morning.