 <unk> a " hybrid storm " , the cyclone rapidly intensified in warm waters of up to 80 ° F ( 27 ° C ) from the Gulf Stream combined with a cold air mass over the United States . The system continued to rapidly intensify while moving within the Gulf Stream ; it developed central convection , an unusual trait for an extratropical cyclone , and at one point exhibited an eye . Despite these indications of tropical characteristics , " There was no front associated with it and it had a warm core , but the radius of maximum winds was more than 150 nautical miles ( 170 mi ; 280 km ) , so under the standard NHC criteria it didn 't qualify as a tropical storm . " On December 23 and 24 , the nor 'easter intensified to attain a barometric pressure of 970 mb ( 29 inHg ) . An upper @-@ level low pressure system that developed behind the storm began to intensify and grew to be larger in size than the original disturbance . In an interaction known as the <unk> effect , the broad circulation of the secondary low swung the primary nor 'easter northwestward towards southern New York and New England . The original low passed along the south shore of Long Island , and made landfall near New York City on December 24 . Subsequently , it moved over southeastern New York State . On December 25 , the system began to rapidly weaken as it moved towards Nova Scotia , before the pair of low pressure systems moved out to sea in tandem in the early hours of December 26 . 
