The winter storm that killed dozens in the United States over the Christmas weekend continued to inflict misery on New York state and air travelers nationwide Tuesday, as stories emerged of families trapped for days during the blizzard of the century. The number of deaths attributed to the winter storm rose to more than 50.<br />''<br />''The problem was compounded when some areas were rendered inaccessible to ambulances for dozens of hours and snowplows were unable to perform their job due to the ferocity of the storm — necessitating rescuers being rescued in some cases.<br />''<br />''The storm of fierce snow squalls, howling wind and sub-zero temperatures forced the cancellation of almost 20,000 US flights in recent days, including more than 3,000 on Tuesday, according to tracking site Flightaware.com.<br />''<br />''US President Joe Biden on Monday approved an emergency declaration for New York state, freeing up funds to help it recover from the disaster.<br />''<br />''A respite of warmer temperatures around 50 degrees Fahrenheit (10 degrees Celsius) was forecast by the weekend, although officials warned that melting snow could result in minor flooding.<br />