High Quality Content by WIKIPEDIA articles! The Effects of Hurricane Irene in New York were the worst from a hurricane since Hurricane Agnes in 1972. Hurricane Irene formed from a tropical wave on August 21, 2011 in the tropical Atlantic Ocean. It moved west-northwestward, and within an environment of light wind shear and warm waters. Shortly before becoming a hurricane, Irene struck Puerto Rico as a tropical storm. Thereafter, it steadily strengthened to reach peak winds of 120 mph (195 km/h) on August 24. Irene then gradually weakened and made landfall on the Outer Banks of North Carolina with winds of 85 mph (140 km/h) on August 27. It slowly weakened over land and re-emerged into the Atlantic on the following day. Later on August 28, Irene was downgraded to a tropical storm and made two additional landfalls, one in New Jersey and another in New York. The storm quickly began to lose tropical characteristics and became extratropical in Vermont.