An area of low pressure destined to become the next typhoon in the western Pacific has its eyes set on slamming Japan Sunday and Monday.
The low spinning north of Guam has already been designated a tropical depression with maximum sustained winds of 56 kph (35 mph) by the Japanese Meteorological Agency.
The Joint Typhoon Warning Center, the official source for AccuWeather.com, has yet to follow suit, though should in the near future.
The AccuWeather.com Hurricane Center expects the low to become not only a tropical depression, but also a tropical storm before the end of Friday local time (Thursday night EDT).
The low should then reach typhoon status before Saturday local time.
Squally and drenching rain bands will continue to spread across the Northern Mariana Islands and Japan's Bonin and Volcano islands as the low strengthens through Saturday. The latter islands are home to Iwo Jima.
The future typhoon is expected to approach Japan later in the weekend before moving into or along the southern and eastern coast of Japan's Honshu island Sunday night through Monday.
The low should be a typhoon when it reaches Japan, then it will weaken and be transitioning to a non-tropical system as it crosses the country.
A band of drenching rain outrunning the low should begin soaking Japan Saturday night with widespread heavy rain along the low's northern and western side to follow for Sunday and Monday. The rain threatens to trigger flash flooding and mudslides.
Damaging winds will also occur along the low's path, while destructive storm surge is a concern along Japan's southern coast--east of the low's center.
Current indications point toward Honshu enduring the brunt of the storm. However, all residents should monitor the progress of the low for potential shifts in its projected track.
For Tokyo, a track immediately to the south of the city would bring the heavy rain and damaging winds directly overhead. A track over or north of the city would spare Tokyo of the heaviest rain, but not the damaging winds. Coastal flooding would become more of an issue with the latter scenario.
Earlier in the week, there was thought that the low would bypass mainland Japan and turn toward Taiwan. That scenario still cannot be totally ruled out but is becoming increasingly less likely.