Former Tropical Storm Shanshan strengthened to a typhoon over the Western North Pacific Ocean south of Iwo To.  At 11:00 p.m. EDT on Friday the center of Typhoon Shanshan was located at latitude 20.5°N and longitude 141.2°E which put the center about 330 miles (535 km) south of Iwo To.  Shanshan was moving toward the north at 14 m.p.h. (22 km/h).  The maximum sustained wind speed was 75 m.p.h. (120 km/h) and there were wind gusts to 90 m.p.h. (145 km/h).  The minimum surface pressure was 974 mb.

Former Tropical Storm Shanshan strengthened to a typhoon south of Iwo To on Friday.  The inner end of a raindband wrapped around the center of Shanshan’s circulation.  A circular eye formed at the center of Typhoon Shanshan.  The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the center of Shanshan’s circulation.  Storms near the center of Shanshan generated more upper level divergence that pumped mass away from the typhoon.  The removal of more mass caused the surface pressure to decrease.

Winds to typhoon force extended out 30 miles (50 km) from the center of Typhoon Shanshan.  Winds to tropical storm force extended out 115 miles (185 km) from the center of Shanshan’s circulation.

Typhoon Shanshan will move through an environment favorable for intensification during the next 24 hours.  Shanshan will move over water where the Sea Surface Temperatures are near 29°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Typhoon Shanshan will intensify during the next 24 hours.

Typhoon Shanshan will move around the western end of a high pressure system over the Western North Pacific Ocean.  The high pressure system will steer Shanshan toward the north-northwest during the next 24 hours.  On its anticipated track, the center of Typhoon Shanshan will be near Iwo To in 24 hours.  Shanshan could approach central Japan in 72 hours.