It moved northwestward , and within an environment of light wind shear and warm waters it steadily strengthened to reach peak winds of NUMBER@1 mph -LRB- NUMBER@2 km/h -RRB- on September NUMBER@3 .

It moved northwestward , and it steadily strengthened to reach peak winds of NUMBER@1 mph -LRB- NUMBER@2 km/h -RRB- on September NUMBER@3 .
