By early on October 17, the outer rainbands, which had previously controlled the structure of the cyclone, dissipated, while deep convection developed near and to the south of the center. Computer models predicted steady strengthening as the depression moved westward before turning to the north. Of the intensity models, the Geophysical Fluid Dynamics Laboratory predicted an intensity of 135 mph (215 km/h) within 36 hours, with other forecasts being more conservative in their predictions. Deep convection continued to develop to the south of the center, and the depression strengthened into Tropical Storm Wilma at 0600 UTC on October 17, while about 200 miles (320 km) southeast of Grand Cayman. Right after becoming a tropical storm, the National Hurricane Center predicted Wilma to track west-northwestward, reaching winds of 105 mph (170 km/h) before striking the northeastern portion of the Yucatán Peninsula. The storm continued to the southwest while deep convection laid near the center. National Hurricane Centner forecaster James Franklin said, "Confidence at the later ranges [of the forecast track] was unusually low", because of wide divergences between computer models. Late on October 17, a Hurricane Hunters flight into Wilma recorded winds of 50 mph (80 km/h), but an unusually low pressure of 989 mbar (29.21 inHg), which would be more typical of a minimal hurricane. This was because of a number of unusual low pressures across the region, which resulted in a lesser pressure gradient and thus lighter winds. Convection continued to develop near the center and became much more symmetrical.