 Tropical Storm Olaf was an erratic and long @-@ lived tropical cyclone that brought heavy rainfall to regions of Mexico , which would be devastated by Hurricane Pauline a week later . The sixteenth named storm of the 1997 season , Olaf formed on September 26 off the southern coast of Mexico . It moved northward and quickly intensified , reaching peak winds of 110 mph (175 km/h) . Olaf turned to the northeast and struck the Yucatán Peninsula on September 28 . It was the first storm to make landfall in Mexico in September since Hurricane Gilma in 1996