Simplify the following text for a Grade 12 native English-speaking person.
Original: The Blizzard of 2003 , also known as the Presidents ' Day Storm II or simply PDII , was a historical and record-breaking snowstorm on the East Coast of the United States and Canada , which lasted from February 14 to February 19 , 2003 .
Simplified: The Blizzard of 2003 , also called the Presidents ' Day Storm of 2003 , or Presidents ' Day Storm II , was a very big snowstorm on the East Coast of the United States and Canada , which started on February 15 and ended on February 18 , 2003 .