Tropical Storm Francisco continues to become better organized as it spins to the southwest of Guam.
Francisco has developed in a similar area to where former Typhoon Wipha formed last week.
Francisco will bring heavy downpours to the Mariana Islands, including Guam, over the next day or two as the storm tracks northward.
During this time, it is expected that Francisco will strengthen into a typhoon, but any damaging winds will remain west of the Mariana Islands.
Later this week into early next week, Francisco will travel over the open waters of the Western Pacific, south of Japan. Conditions appear to be favorable for Francisco to strengthen further during this time as Francisco takes a track very similar to that of former Typhoon Wipha.
By early next week, Francisco will begin to interact with a frontal boundary to the north that approaches Japan. This will front will attempt to steer Francisco northward then turn the storm northeast toward southern and eastern Japan.
Depending on the exact timing of the front coming in from the west, Francisco could be guided on a track very similar to the one taken by Wipha.
If this scenario unfolds, another round of flooding rain and damaging winds would slam eastern Japan, including Tokyo.
If Francisco were to miss the connection with this frontal boundary, the storm would likely slow in speed and track off to the west before being lifted northward by a later frontal boundary.
This would likely take the greatest impacts of Francisco into the Korean Peninsula or western Japan, similar to the track of Tropical Storm Kong-Rey, earlier this year.