Both the system in the Gulf of Mexico and the system in the Midwestern United States were supported by the same shortwave trough.
Due to blocking steering patterns, both storms began to gravitate towards the Eastern Seaboard.
The HPC began issuing periodic storm summary bulletins on the two low-pressure areas at 0300 UTC on February 8.
Their forecasts suggested that the system associated with the subtropical jet stream would rapidly intensify near the United States East Coast, later absorbing the system associated with the polar jet stream.
The already existing Cold weather health alert was extended in anticipation of the storm.The nor'easter's effects in the United States received a Category 3 rank on the Northeast Snowfall Impact Scale, classifying it as a "Major" Winter Storm. The second low, originating across the state of Texas, produced heavy rains and flooding across much of the Southeast and Mid-Atlantic parts of the U. As the two systems merged off the Northeast coast on February 8, 2013, they produced heavy snowfall over a large region from North Jersey and inland from New York City through eastern New England up to coastal Maine and inland to Ontario.The first low-pressure system, originating from the Northern Plains of the United States, produced moderate amounts of snow across the Great Lakes region of the U. Total snowfall in Boston, Massachusetts, reached 24.9 inches (63 cm), the fifth-highest total ever recorded in the city.A few hours later, the southern disturbance began a phase of barometric deepening as it tracked northeastward off the Outer Banks, while the northern system maintained an easterly course into northwestern Ohio.Beginning at 0000 UTC on February 9, the two systems began an extensive merging process, with the strengthening cyclone originating from the subtropics absorbing energy from the cyclone originating from the polar jet stream.