February 1983 North American blizzard

A blizzard in February 1983, nicknamed the "Megalopolitan Blizzard", impacted the Mid-Atlantic, Northeast, and New England regions of the United States. First developing as a low-pressure area on February 9 while a El Niño event ensued, the low then moved eastward across the Gulf of Mexico. While the low progressed across the Gulf, several tornadoes associated with the system touched down across Texas, Louisiana, and Florida, ultimately resulting in ten injuries. The low then emerged over the Atlantic Ocean near the Georgia–South Carolina border, later developing and intensifying into a cyclone as it moved parallel along the East Coast of the United States. The cyclone then moved northward while producing blizzard conditions and heavy snowfall across portions of the Mid-Atlantic on February 11, including across Maryland and northern Virginia. Continuing to intensify and moving northward, the cyclone then brought heavy snow and blizzard conditions to parts of the Northeast and New England. Overall, the blizzard caused 46 deaths and set multiple weather records in terms of snowfall.

Meteorological synopsis
In 1982 and 1983, a strong El Niño occurred, including on the dates during the blizzard's occurrence, which led to above-average temperatures across the northern United States and a cooler and wetter weather pattern across the South. On February 9, a low-pressure area formed, centered over eastern Texas and along the Texas-Gulf of Mexico coastline. It then progressed eastward across the Gulf the next day before moving across the Southeastern United States and emerging in the Atlantic Ocean off the Georgia-Florida coast. The low-pressure system then intensified and fully developed into a cyclone as it approached Cape Hatteras, North Carolina. As the cyclone moved northward along the East Coast of the United States, snow fell across the Mid-Atlantic beginning on February 11, with some areas experiencing blizzard conditions. The cyclone then produced snow and blizzard conditions across portions of the Northeastern United States and New England regions, continuing to intensify as its pressure dropped to 1003 millibars by February 12. The low's pressure continued to drop on that day while reaching portions of southern New England before tracking offshore northward off the New England coast. The blizzard was nicknamed the "Megalopolitan Blizzard" after the system hit numerous metropolitan areas along the East Coast of the United States with 30-75 cm of snow.

Mid-Atlantic
In preparation of the blizzard in Virginia, Eastern Mennonite University and James Madison University were closed, with the latter cancelling its classes for the first time since the Ash Wednesday Storm of 1962. At Richmond International Airport in Richmond, 17.7 in of snow fell, which was the third-highest snow accumulation in the city on record. Daily snowfall records were set in Lynchburg and Roanoke, where 14.6 in and 18.4 in of snow fell in 24 hours, respectively. The heaviest snow fell in Woodstock, where 32 in of snow accumulated. The cyclone caused the SS Marine Electric, a merchant ship, to capsize, killing 31 of the 34 onboard and prompting an investigation into the incident and the ship's design itself by the United States Coast Guard's board of inquiry. As a result of the sinking, the Coast Guard's inspection procedures were modified and new additions and requirements were introduced to the maritime law enforcement's marine safety guideline.

In Maryland, 22.8 in of snow fell in Baltimore, which was the second-highest snowfall after the Knickerbocker storm in 1922. Some areas in Frederick and Montgomery counties in Maryland had their heaviest snowfall on record. In Washington, D.C., 16.4 in of snow fell, closing Baltimore/Washington International Airport, Dulles International Airport, and Ronald Reagan Washington National Airport and shutting down the Washington Metro. Numerous vehicle accidents occurred in West Virginia, as there were more than 34,000 homes without power across Charleston and Pineville. Among the highest snow accumulations from the blizzard occurred in Glengary, West Virginia, where 35 in of snow accumulated. In Windsor Locks, Connecticut, a record 19 in of snow fell in 12 hours.

Northeastern United States
In Lancaster, Pennsylvania, the snow prompted firefighters and emergency management to sleep in the fire department's halls to prepare for emergencies. On February 11, the heavy snowfall also cancelled Ronald and Nancy Reagan's trip to Camp David, causing Secretary of State George Shultz to be invited for dinner and marking the beginning of the shift towards ending the Cold War. The blizzard also produced 21 in in Springfield, Massachusetts, the third-highest snowfall total there since 1905 as of 2013, and resulted in thousands of people being stranded at an Aerosmith concert. The concert itself was delayed by more than an hour after the band's lead singer, Steven Tyler, arrived late because of the blizzard. The blizzard produced the same snowfall total in Springfield, Massachusetts, as at Bradley International Airport in Hartford, Connecticut, which is recorded as the fourth-highest snowfall total there as of 2015. Hundreds of vehicles were abandoned on the Staten Island Expressway as heavy snowfall rates occurred and up to 22 in of snow fell. In Central Park, 17.6 in of snow fell, which is the thirteenth-highest snowfall accumulation there since 1869 as of 2021. Twenty-four-hour snowfall records were set in Allentown, Harrisburg, and Philadelphia, with all three cities receiving more than 20 in of snow. In Allentown and Bethlehem, 5 in of snow fell in one hour. At Harrisburg International Airport, 25 in of snow fell, which is the second-highest snow accumulation across the Susquehanna Valley. Lightning also occurred during the blizzard in some areas across the Northeast.

Several airports were closed as a result of near-zero visibility caused by the heavy snowfall, including LaGuardia Airport, Newark Liberty International Airport, and John F. Kennedy International Airport across the New York metropolitan area, as well as Philadelphia International Airport in Philadelphia. Multiple departing flights from Wilkes-Barre/Scranton International Airport were cancelled, and the Pennsylvania State Police noted that Interstate 80 "closed itself". Businesses and schools across Pennsylvania were closed, and Interstate 95 in Philadelphia was closed. A snow emergency was declared in New York City, as well as a state of emergency for several areas in New Jersey, including Trenton.

Tornado outbreak
Prior to 1990, there is a likely undercount of tornadoes, particularly E/F0–1, with reports of weaker tornadoes becoming more common as population increased. A sharp increase in the annual average E/F0–1 count by approximately 200 tornadoes was noted upon the implementation of NEXRAD Doppler weather radar in 1990–1991. 1974 marked the first year where significant tornado (E/F2+) counts became homogenous with contemporary values, attributed to the consistent implementation of Fujita scale assessments. Numerous discrepancies on the details of tornadoes in this outbreak exist between sources. The total count of tornadoes and ratings differs from various agencies accordingly. The list below documents information from the most contemporary official sources alongside assessments from tornado historian Thomas P. Grazulis.