Typhoon Ampil passed east of Tokyo on Friday morning.  At 11:00 a.m. EDT on Friday the center of Typhoon Ampil was located at latitude 35.4°N and longitude 142.5°E which put the center about 130 miles (210 km) east of Tokyo, Japan.  Ampil was moving toward the northeast at 14 m.p.h. (22 km/h).  The maximum sustained wind speed was 120 m.p.h. (195 km/h) and there were wind gusts to 150 m.p.h. (240 km/h).  The minimum surface pressure was 944 mb.

Typhoon Ampil was the equivalent of a major hurricane when it passed east of Tokyo on Friday morning.  Bands in the western part of Ampil’s circulation brought gusty winds and locally heavy rain to coastal parts of central Honshu.  The airport at Narita reported a sustained wind speed of 32 m.p.h. (52 km/h) and a wind gust of 52 m.p.h. (83 km/h).

A large circular eye was present at the center of Typhoon Ampil.  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 revolved around the core of Ampil’s circulation.  Storms near the core generated upper level divergence that pumped mass away from the typhoon.  The removal of mass in the upper levels of the atmosphere was almost in balance with the inflow of mass in the lower atmosphere.

The circulation around Typhoon Ampil was large. Winds to typhoon force extended out 50 miles (80 km) from the center of Ampil’s circulation.  Winds to tropical storm force extended out 150 miles (240 km) from the center of Typhoon Ampil.

The Hurricane Intensity Index (HII) for Typhoon Ampil was 22.1.  The Hurricane Size Index (HSI) was 17.0 and the Hurricane Wind Intensity Size Index (HWISI) was 39.1.  Typhoon Ampil was similar in intensity to Hurricane Delta when Delta hit Louisiana in 2020.  Ampil is larger than Delta was.

Typhoon Ampil will move through an environment that will become less favorable for intensification during the next 24 hours.  Ampil will move over water where the Sea Surface Temperatures are near 30°C.  It will move under the upper level westerly winds in the middle latitudes.  Those westerly winds will cause the vertical wind shear to increase.  The increase in vertical wind shear will cause Typhoon Ampil to start to weaken during the next 24 hours.

The westerly winds in the middle latitudes will steer Typhoon Ampil toward the east during the next 24 hours.  On its anticipated track, Typhoon Ampil will move away from Japan.