My theory comes from the belief that the storms we experience today are relatively weak compared to the storms that may have happened in the past.
The storm will most likely attain a hurricane structure the size of or bigger than Texas. At the eye wall of the storm, cloud tops will reach heights of more than 70,000 feet. It will cause major flooding due to torrential rain, and damage because of wind and hail. The only issue is that the storm will need some extreme events for it to occur. These ingredients include: A year of extremely calm weather with at most only 400 tornadoes recorded, a week of 100+ degree temperatures (°F), 90 to 100% humidity for a week, a residual low pressure system over the central U.S., and a solar flare capable of causing a world-wide power outage.
A week before the storm, temperatures will skyrocket to 100+ °F due to a solar flare, for solar flares tend to increase worldwide temperatures. The extreme humidity and heat will cause a relatively large tornado outbreak of about 250+ tornadoes. Following the outbreak, a Multi-bow Serial Derecho with winds of 100+ mph will form in the Gulf and travel up along the eastern U.S., knocking out power in at least 20 states. Next, the residual low pressure over the U.S. will strengthen and collect moisture to become what l'd call a "Super Multi-cellular Storm Complex". It will quickly wrap around the low-pressure and attain it's hurricane-like structure. Unlike a hurricane, however, the eye of this storm is not calm, for it's eye wall will rotate so rapidly that it touches the ground becoming a tornado with winds exceeding 400 mph. It will then travel southwest-northeast from the Texas-Oklahoma border. In only four days, this storm will have enough energy to produce 36,000+ tornadoes, before dissipating over the Atlantic. By roughly calculating the wind patterns this storm will cause, it's path will bring it's eye-wall directly over New York City.